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2010GeoStrata_JanFeb.indd 1 10/29/09 3:17:37 PM

th 44 U.S. Rock Mechanics Symposium Salt Lake City, Utah USA June 27-30, 2010

Geomechanics Workshop (free with Registration) Dr. Priscilla Nelson-Moderator Dr. Don Banks Dr. John Curran Dr. Maurice Dusseault Dr. Richard Goodman Dr. William Pariseau

Over 400 Abstracts Submitted

Opening Reception—Richard Robbins “Advancements in Boring”

Keynote—Prof. John Hudson “Rocky Rambles through Caves, Cathedrals and Caverns”

Goodman Geologic Hazards Tour Professor Richard Goodman and Dr. Richard Allis

Commercial Exhibits-Video Presentations

Tours: Kennecott Copper Mine and TerraTek Golden Spike Monument, The Nature Conservancy Great Salt Lake Project and the Spiral Jetty Park City, Olympic Winter Park, Factory Outlet Mall Mormon Genealogy Library and Temple Square

Registration online at www.armasymposium.org or 1-703-683-1808, Peter Smeallie / ARMA Executive Director Figure 4. Shear stiffness degradation of London . Features VOLUME 14 l ISSUE 1 Gsec p′ 600 Shear Stiffness nonlinear elastic 400 16 It’s All the RAGE CAU compression test By D.V. Griffiths, Ph.D., P.E., F.ASCE and 200 CAU extension test Gordon A. Fenton, Ph.D., P.Eng., M.ASCE 0 0.001 0.01 0.1 1.0 Shear strain (%) 32

22 Using Inversion to Improve Prediction in Geoenvironmental Engineering By Craig H. Benson, Ph.D., P.E., D.GE, F.ASCE and Ronald J. Breitmeyer

28 Using Numerical Analysis in Practice By Lidija Zdravkovic’ , Ph.D., DIC and David M. Potts, Ph.D., DSc, FREng Seismic Data Figure 3. Seismic data indicates po- tential faults in the reservoir, but not No potential faults36 Advancing the Practice of Analysis the caprock (at top). By Scott Anderson, P.E., M.ASCE Indications of predom- 37 inant fracture orienta- tions are shown on FMI logs (at bottom). (Data courtesy 42 CO2 Sequestration: Fractures Are Enabling of ISG CO2 JIP). Clean Energy Options By Joseph Morris, Ph.D., and Laura Pyrak-Nolte, Ph.D.

ON THE COVER: A voxelization of aerial laser scanning of downtown Dublin. It is a critical step in the auto-generation of city-scale, finite element models for the prediction of tunnel- induced subsidence along the proposed metro route. Image by Tommy Hinks, 42 43 Debra Laefer, and Hamish Carr funded by Science Foundation Ireland.

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Civil Engineering-January-final.indd 1 12/5/09 11:34:56 PM Departments 08 Thoughts from the President

10 From the Editorial Board

14 Commentary: The Role of Analysis and Modeling in Geotechnical Design in the 21st Century 21 By Rodrigo Salgado, Ph.D., P.E., M.ASCE, and Patrick J. Fox, Ph.D., P.E., M.ASCE

21 GeoPoem

49 GeoCurmudgeon

52 CoreBits 49

WHO’S WHO AT GEO-STRATA

EDITORIAL BOARD Debra F. Laefer, Ph.D. 2010 GI BOARD OF GI STAFF ADVERTISING University College of Dublin GOVERNORS SALES MANAGERS James L. Withiam, Ph.D., P.E. , D.GE 011.353.86.343.3088 Carol W. Bowers, P.G., CAE, IOM D’Appolonia [email protected] Edward Kavazanjian, Jr., Ph.D., P.E., D.GE, Director Jennifer Wirz 412.856.9440 President [email protected] 214.291.3652 [email protected] William K. Petersen, P.E. URS Corporation Jean-Louis Briaud, Ph.D., P.E., D.GE, Past Linda R. Bayer, IOM Ellen Tucker N. Catherine Bazán-Arias, Ph.D., P.E. 215.390.2157 President Manager and Production 214.291.3661 DiGioia, Gray & Associates, LLC [email protected] Larry P. Jedele, P.E., Treasurer [email protected] 412.372.4500 ext. 119 Erin Ladd [email protected] Veronica L. Streich, P.E. Craig H. Benson, Ph.D., P.E., D.GE Suzanne Davenport 214.291.3653 HNTB Corporation Content Coordinator Je Dunn, Ph.D., P.E., G.E. 414.359.2300 William M. Camp, III, P.E., D.GE [email protected] Je Sanderson Kleinfelder, Inc. [email protected] Moustafa A. Gouda, P.E., F.ASCE, D.GE 703.295.6107 510.628.9000 Dianne Vance [email protected] Bruce Gossett Philip G. King, P.E., D.GE Director of Advertising Publisher Carol W. Bowers * P.G., CAE, IOM, Secretary 703.295.6234 703.295.6311 Geo-Institute Website *ex-o cio, non-voting member www.geoinstitute.org

Geo-Strata is a forum for the free expression and interchange of ideas. The opinions and positions stated within are those of the authors, and not necessarily those of Geo-Strata, the Geo-Institute, or the American Society of Civil Engineers (ASCE). Geo-Strata—ISSN 1529-2975—is published bi-monthly by ASCE, 1801 Alexander Bell Drive, Reston, VA 20191-4400 and is a free ASCE/Geo-Institute membership benefit, not available by subscription. ADDRESS CHANGES: ASCE/G-I members should e-mail [email protected], or click on “My Profile” at asce.org. Copyright © 2010 by the American Society of Civil Engineers. All rights reserved. Materials may not be reproduced or translated without written permission from ASCE. Periodicals postage paid at Herndon, VA, and at additional mailing offices. POSTMASTER: Send address changes to Geo-Strata, 1801 Alexander Bell Drive, Reston, VA 20191-4400.

4 Geo-Strata l geoinstitute.org Departments TR ANSFOR M YOUR DAT A INT O KNOWLED GE PLog Enterprise YOUR GEOTECHNICAL KNOWLEDGEBASE™ The PLog Enterprise KnowledgeBase™ transforms your data into an New invaluable asset for your organization by combining all of your individual gINT projects into a single database. By archiving your geotechnical data in the PLog Enterprise KnowledgeBase™, it becomes more than just data; it becomes information and a resource for your organization that will continue to grow in value over time. Whether you have hundreds or thousands of projects you can turn your geotechnical information into knowledge that bene ts your organization. For more information, please visit: www.dataforensics.net/enterprise.php

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DAT A.O N PURPOSE. Letters to the Editor

November/December 2009

I just wanted to let you know how other “patching,” the prominence fi nally much I enjoyed your article “Carving came crashing down. This occurred the World’s Largest Rock Monument.” You many years after I had moved back west. really captured the essence of the project. It was a sad day for those of us who were Fascinating! so accustomed to seeing this impressive natural visage daily. I moved from Boulder to Franconia, New Hampshire many years ago to Thanks to your crafted article, teach at Franconia College. There was I now look forward to seeing ol‘ Chief an iconic natural rock formation of a Crazy Horse in person one of these days. “face” on Cannon Mountain in the White Mountains, located at the top of the pass approaching Franconia called “The Old S. Scot Litke Man of the Mountain.” Unfortunately it Publications Manager, ADSC succumbed to the forces of nature, mostly Dallas, TX water seepage in fractured rock, and, after many years of rock bolting, grouting and “The Old Man of the Mountain”

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6 Geo-Strata l geoinstitute.org

Thoughts from the President Ed Kavazanjian, Ph.D., P.E., D.GE

Predicting (or Inventing) the Future student-related activities at the G-I annual Congress. The GeoFlorida Congress will include a reception for student My morning radio station used to have a news attendees with our Organizational Members, a Career commentator, Scoop Nisker, who closed his newscasts Fair, increased participation in the MSE wall competition with the suggestion that “If you don’t like the news, go out for students, and a student poster session that will be and make some of your own.” To paraphrase Scoop, “If tied in with the MSE wall competition. Expansion of the you are concerned about the future, scope of the Committee to include go out and create one that is to your younger members will help provide liking.” Or, to quote Alan Kay, “The a seamless transition from student best way to predict the future is to membership to active engagement invent it.” (Alan Kay was one of the in the Geo-Institute for the next inventors of Smalltalk, the inspiration generation of volunteers and leaders and technical basis for the MacIntosh in our Society. and subsequent windowing-based operating systems). Other recent student-related initiatives of the G-I include the The Geo-Institute is engaged in expansion of the number of G-I a number of activities designed to Graduate Student Organizations invent the future we want for our (which now stands at eight) and the organization. But for any of these formation of the Student Presidential activities to be successful, they require Group by Jean-Louis Briaud during the active engagement of our members his presidency (and continued during through volunteer activities. You can my term). These initiatives represent help create the future you would like important steps in developing the for the G-I by becoming more active next generation of leaders for the G-I in your local ASCE geotechnical and providing some fresh, new ideas group (which hopefully is either for engaging our student and younger currently a local G-I chapter or on members. its way to becoming one), joining a technical committee on the national level (you can To help provide a reliable source of funding for download an application at http://content.geoinstitute.org/ our student activities, the Board of Governors created committees/committees.html, or by volunteering to serve in a restricted Student Participation Fund and obtained one of the many other G-I activities that rely upon member permission from ASCE to channel all of the voluntary participation, e.g. on a Board of Governor task force, contributions made to the G-I with your annual dues the organizing committee for an upcoming G-I annual payment into this fund. If you have not yet made your Congress or specialty conference, or the Editorial Board for dues payment, please consider a voluntary contribution. one of our journals or Geo-Strata. You can also encourage If you have already paid your dues and missed the and support involvement by your colleagues and employees opportunity to contribute to the fund, you can make a in these G-I activities. direct contribution through the G-I website. Click on the “donate online” link in the associated story at www. One of the most important recent initiatives designed to geoinstitute.org. Your contributions, as well as the activities invent the best possible future for the Geo-Institute is our described above, will help us continue to develop the next Student and Younger Member Participation Committee. generation of volunteers and leaders of our organization, This is a Board-level committee initially formed as the thereby inventing the future we want for the Geo-Institute. Student Participation Committee but recently expanded in scope to include younger members. The long-term success of any organization relies upon a continuing stream of new blood and fresh ideas, and this committee is designed to foster the development of that stream. The Committee has made impressive progress towards that goal in its fi rst few Ed Kavazanjian, Ph.D., P.E., D.GE years of operation, including a signifi cant enhancement of President, Geo-Institute of ASCE

8 Geo-Strata l geoinstitute.org gINT Ad Bentley Solution.pdf 1 1-12-2009 19:58:44

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K From the Editorial Board

Analysis, modeling, and design; in many ways that’s the (running a model “in reverse” to find the set of input essence of what we do as a profession. Analysis, modeling, parameters that result in the prediction that most closely and design is also the theme of this issue and GeoFlorida resembles observed behavior) can be a powerful tool to 2010 to be held in West Palm Beach in February. As many improve parameterization. of the articles in this issue recount, our ever-improving computational capabilities must be used with care, for just A number of specialist geotechnical software packages as we once used back-of-the-envelope checks of our slide are currently available. They usually differ in the level rule analyses, we must take at least equivalent care with of sophistication and in the way in which constitutive our analytical tools. This issue tries to capture some of models, boundary conditions, and numerical solvers these concerns and some of what you’ll learn if you attend are implemented so it is not unusual to obtain different GeoFlorida 2010. answers to the same problem from different software. For a successful analysis, it is also important for the What’s Inside? user to understand how the applied software works and what might be At the time of Terzaghi’s seminal going on in the computer black box. text Theoretical and Lidija Zdravković and David Potts for about the next 20 years into discuss some of the problems and the early 1960s, the discipline was solutions involved with one of the dominated by theory supported by simplest geotechnical constitutive simplified methods of analysis and models, the linear elastic-plastic Mohr- empiricism. Since then, we have Coulomb model in “Using Numerical seen computational power continue Analysis in Geotechnical Engineering to increase, constitutive models Practice.” developed that realistically model soil behavior, and numerical methods Recent flood zone mapping shows evolve to analyze the boundary-value that 42 miles of containing problems of geomechanics. But where the Sacramento Natomas Basin do is this all headed, especially for more not provide a 100-year level of flood routine projects with small budgets? Rodrigo Salgado and protection. An on-going engineering evaluation of levees Pat Fox offer their perspective in this issue’s commentary, is providing a unique opportunity to improve the state “The Role of Analysis and Modeling in Geotechnical Design of geotechnical practice in terms of levee analysis and in the 21st Century.” design. In “Advancing the Practice of Levee Analysis,” Scott Anderson describes side-by-side comparisons of Risk assessment in geotechnical engineering, or RAGE, widely used and slope stability modeling and is a rapidly growing area of interest and study. This is analysis software to assess short- and long-term scenarios, driven by the inherent uncertainty of geologic materials conduct probabilistic vulnerability studies to quantify and our ever-improving probabilistic tools to characterize relative reliability of embankments, and develop accurate, and quantify uncertainty and apply them in geotechnical efficient, and presentation-ready answers to highly complex analysis and design. In “It’s All the RAGE,” Vaughan problems. Griffiths and Gordon Fenton describe some of these tools and their ever-increasing importance in more conventional Our last article is not about this issue’s theme, but projects where engineers are increasingly required to rather last issue’s theme, rock mechanics. Sequestration of explicitly consider risk and reliability in their analyses and carbon dioxide in deep geologic reservoirs has emerged as a designs. method to enable substantial reductions in greenhouse gas emissions. Joe Morris and Laura Pyrak-Nolte introduce the The processing capability of today’s computers and process and the importance of geologic characterization in

the availability of sophisticated numerical models permit “CO2 Sequestration: Fractures Are Enabling Clean Energy the solution of complex problems in geoenvironmental Options.” engineering. But how realistic are the solutions they provide and how can they be tested? In “Using Inversion to Improve If you could choose another time to be a geotechnical Prediction in Geoenvironmental Engineering,” Craig (or soil mechanics) engineer, when would that be? Our Benson and Ronald Breitmeyer describe how inversion Geo-Poet has chosen 1965. Read “Confessions of a Young

10 Geo-Strata l geoinstitute.org Luddite” to find out why. And how many times have you been told that perception is reality? Our For over 14 years GEOVision has specialized in non- GeoCurmudgeon “perceives” that invasive methods of investigation for engineering, geoprofessionals don’t get the respect environmental, and ground water applications including: they should because we don’t show up and speak up before the public to �  Characterization of disposal areas influence the public discourse. Please �  Contaminant detection and monitoring check them out and let us know your �  Subsurface geologic and hydrologic conditions preferred geo-era and what you’ve �  Subsurface infrastructure done to show up and speak up. �  Engineering properties of soil and rock �  hazard This message was prepared by Jim Withiam, Editor-in-Chief. NEW TOOLS! call for information on... OYO PS Suspension Logger (we now have four!) Please Renew ALL surface wave methods (SASW, MASW, ReMi, Array) Other Borehole Geophysics, including Televiewer Your 2010 ASCE/ 1124 Olympic Drive, Corona, CA 92881 (951) 549-1234 fax (951) 549-1236� Geo-Institute www.geovision.com

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Geo-Strata l geoinstitute.org 11 A Diplomate of Geotechnical Engineering Profile… Blaine Leonard, P.E., D.GE., F.ASCE, President ASCE

Why D.GE and require it as part of their selection processes. Since Certification? certification of geo-professionals is still fairly young, we haven’t seen that ideal reached yet. I hope that someday we Certification is will. a demonstration of When you enter a doctor’s office, you will often notice expertise and experience a Board Certification designation hanging on the wall. We in a specialized field. It are more comfortable after seeing that, knowing that we are sets us apart from those about to be diagnosed and treated by someone with special who have not attained expertise. It should be no different in engineering; clients this level. should recognize and require the D.GE credential. Ideally, clients will recognize the value of My Background specialty certification, My practice has been quite broad. I have been in both the private and public sectors. I have practiced geotechnical engineering on a variety of projects, and in many other civil engineering areas.

The geotechnical background has always been useful to me. Although I am interested in many things, my passion is still geotechnical engineering, and I find the most satisfaction on those projects.

What D.GE Certification Has Meant to Me

I will have to admit that being a D.GE has not as yet provided me any direct benefit over the past year. However, I am proud to hold that credential, and to display it on documents that bear my name. As I continue in my career, I am sure that it will provide an indication of my background and focus, and will help me in the projects I pursue. I will Specialized Site Investigation Services encourage others who are qualified to seek specialty certification, and West 1-800-567-7969 • East 1-800-504-1116 will promote its use in selection www.conetec.com • [email protected] processes.” Vancouver, BC • Edmonton, AB • Salt Lake City, UT • West Berlin, NJ • Charles City, VA

12 Geo-Strata l geoinstitute.org

Commentary: The Role of Analysis and Modeling in Geotechnical Design in the 21st Century

By Rodrigo Salgado, Ph.D., P.E., M.ASCE, and Patrick J. Fox, Ph.D., P.E., M.ASCE

With GeoFlorida 2010, which focuses on analysis, While this role of theory was certainly appropriate for an modeling, and design, fast approaching, it is worthwhile engineer of the 1950s, when soil models, site investigation to consider the role that analysis or “theory” in its various methods, and computational methods were all too forms has played and will play in design in the future. For crude to provide accurate solutions for real problems, the purposes of this discussion, we fi nd it convenient to an upgrade of the role of theory in the design process is mark the beginning of our discipline appropriate with the tools available with the publication of Karl today. Given the limited scientifi c Terzaghi’s Theoretical Soil Mechanics in knowledge and limited software 1943; this means that, at 67 years old and testing resources of the early in 2010, geotechnical engineering is days of geotechnical engineering, a bit younger than some of its more empiricism was all an engineer senior professionals! had available. While empiricism can provide acceptable solutions, it Terzaghi’s book was the must be moderated by judgment, fi rst organized effort to catalog particularly when one is operating the theories that helped guide outside the range of conditions used geotechnical design at the time. If we to develop the empirical rules. But examine the status of theory in the today the question is whether theory 1940s and 1950s, before the age of has developed to the point that it computers, the prevalent method of can take on a greater role in practice analysis was limit equilibrium, and than it has in the past, thereby also soil was modeled as either linear redefi ning the roles of empirical elastic or perfectly plastic (according precedent and judgment. to Terzaghi, a soil had to be modeled as an “ideal ” or “ideal clay,” An examination of the literature for it was impossible to capture shows: 1) that the behavior of soil at mathematically the complexity of the elemental level is reproducible soil behavior). In contrast, today using constitutive models that have we have considerable and growing parameters with physical meaning computational power, constitutive and that can be determined models that can realistically model soil behavior, and a relatively simply; 2) that computational techniques exist variety of analytical methods, chief among them the fi nite to integrate these constitutive models and also handle the element method, to analyze the boundary-value problems nonlinearities that appear in most geotechnical boundary- of geomechanics. value problems and, most importantly; 3) that predictions made with analyses using these models and techniques The enormous progress that has taken place in match measurements in well-controlled experiments. Thus, theoretical soil mechanics (particularly in the last 30 years) if the essential ingredients of quality site characterization has yet to be substantially integrated into practice, and and testing are added to this mix, conditions are in thus the role that theory plays in the design process is not place for design work to be conducted at a high level of signifi cantly different from what it was decades ago. One of sophistication. Of course, judgment still has a role in the reasons for this relatively slow integration of advances the design process to prevent blunders, avoid the use of in theory into practice is the dominant philosophy followed inappropriate tools, and refi ne solutions. However, the role in some of the earlier geotechnical texts. Although Terzaghi of judgment would not be to replace calculation tools. had a confl icted relationship with the value of theory in soil mechanics, sometimes pointing out how essential it was The technical problems that our profession is likely and sometimes downplaying its value, the approach taken to face in the future will be more challenging than in the in both Theoretical Soil Mechanics and Soil Mechanics in past. It is also obvious that most projects have insuffi cient Engineering Practice that theory provides some guidance but, budget or time to allow for sophisticated analyses. So, in the end, solutions are mostly shaped by judgment and empiricism, has attracted the largest audience. Continued on page 20

14 Geo-Strata l geoinstitute.org

It’s All the RAGE

By D. V. Griffiths, Ph.D., P.E., F.ASCE and Gordon A. Fenton, Ph.D., P.Eng., M.ASCE

R isk assessment in geotechnical engineering, or RAGE, of geotechnical systems will typically include a target is an exciting and rapidly growing area of interest and study acceptable risk, defined as the risk that the stakeholders for both geotechnical practitioners and academics. Evidence consider acceptable under given conditions. The acceptable of this growth is attested by increased sessions on the topic risk built into a design will likely be much lower for a major at G-I symposia, new practitioner-oriented journals, recent earth dam in a populated area than for an textbooks, and regularly scheduled ASCE Continuing retaining an irrigation pond in a remote rural location. Education short courses. Regardless of the type of project, however, risk assessment is unavoidably quantitative in nature and an engineer and rocks in their natural state are among the most performing a risk assessment must ultimately develop variable of engineering materials. Geotechnical engineers numerical estimates of pf.. often must “make do” with materials at a particular site. In a perfect world with no economic constraints, numerous Methods of Probabilistic Analysis would be drilled and multiple samples returned to the laboratory for measurement of soil properties While there are several tools available for probabilistic such as permeability, compressibility, and . analysis in geotechnical engineering, event trees, the first Engineering designs following such a thorough site order reliability method, and the random order finite characterization would lead to confident performance element method of probabilistic analysis, are representative predictions. In reality, rather limited site investigation data of tools with increasing levels of complexity and are available and the traditional approach for dealing with mathematical sophistication. uncertainty in geotechnical design has been through the use of characteristic values of the soil properties coupled with a Level I: Event Trees. Event trees are typically used for generous factor of safety. probabilistic analysis in practice, and are performed prior to deciding whether more detailed mathematical or numerical If the multitude of data for one of the soil properties modeling is warranted. Agencies such as the Bureau of from the “perfect world” site investigation were plotted as Reclamation who deal regularly with critical geotechnical a histogram, a broad range of values would be observed structures, such as earth dams, use event trees to estimate in the form of a bell-shaped curve. The most likely values the probability of different modes of design failure. of the property would be somewhere in the middle, but a significant number of samples would display higher and Event trees consist of nodes and branches that must lower values. This variability, inherent in soils and rocks, be constructed carefully and adhere to certain rules to be suggests that geotechnical systems are highly amenable to a useful in calculations. From a starting node, two or more statistical interpretation. branches leave. At the end of each branch there is another node from which more branches may leave and go to This is quite a different philosophy to the traditional separate nodes. The idea is repeated from the newer nodes approach: in the probabilistic approach, input soil as often as required to completely depict all possibilities. properties are characterized in terms of their means, A probability is associated with each branch and, for variances, and covariances, leading to estimates of the all branches except those leaving the starting node, the probability of failure (pf) or reliability index (ß) of a probabilities are conditional; that is, they are probabilities design. Specific examples might involve estimation of the of events occurring given that other events (earlier probability of failure of a slope, the probability of excessive branches) have already occurred. differential settlement of a foundation, or the probability of excessive leakage from a reservoir. Event trees can become quite complicated for complex problems. Figure 1 presents a simple example for an Risk is defined as the probability of design failure embankment potentially vulnerable in the event of an weighted by the consequences of design failure (e.g., earthquake or a flood. All the numbers on the figure fatalities, cost, and unacceptable performance). Design represent probabilities, which in practice are developed by

16 Geo-Strata l geoinstitute.org probabilistic models and/or an expert panel of engineers where FS = qult/qall and qult is obtained from Terzaghi’s based on experience and similar case histories. equation. Let us assume that the width of the footing (B), the soil unit weight (γ’), surface surcharge (q) and groundwater conditions are confidently known (deterministic), but that the shear strength parameters ( Embankment Failure c’, tanΦ’) are uncertain and to be treated as random input Failure 0.3 Event Tree variables (stochastic), characterized by their means and

standard deviations (µc′,σc′) and (µtanφ′, σtanφ′). Earthquake 0.1 Not Failure 0.7 Failure 0.2 A typical bivariate probability density function with Flood 0.3 generic random variables x and y might look like the “hill” Not Failure 0.8 shown in Figure 2a. Figure 2b shows a plan view of the probability density function in normalized space Neither 0.6 Failure 0 (µ = 0, σ = 1) together with contours of the reliability index ß, which

Not Failure 1 measures standard deviations units away from the mean. For example, the contour marked ß = 1.5, represents the locus of random variables 1.5 standard deviations away from their mean values. Also shown on Figure 2b is the Figure 1. A simple event tree showing conditional probabilities performance function labeled FS = 1. that might lead to failure of an embankment.

The probability of a specific type of failure is found by Probability Density Function multiplying together the probabilities along the branches and Performance Function that lead to that failure. From Figure 1, the probability of

failure due to an earthquake (pfeq) would be given by:

pfeq = 0.1 x 0.3 = 0.03

0.07 The total pf, regardless of cause, would be obtained by adding together the branch products due to earthquake and flood as:

pf = 0.1 x 0.3 + 0.3 x 0.2 = 0.09 10 8 6 4 2 0 Level II: First Order Reliability Methods (FORM). This method has gained significant attention in recent years as y x a relatively simple way of obtaining probabilities of failure Figure 2b. for geotechnical systems involving random input variables. L 0 2 4 Plan 6 8view 10 of a nor- Figure 2a. Probability malized pdf together The method is also easily run using familiar software such density function (pdf) involving with a performance two random variables function marked as Excel. FS=1 and the mini- mum reliability index

contour marked The starting point for a FORM analysis is a performance β=0.6892. L

function for the system under investigation. A performance 2 3.5 function separates safe from failure combinations of input 1.5 3 variables and is the locus of FS = 1. Usually, the function 2.5 2 1 is arranged such that if it is negative, failure conditions 1.5 .6892 are implied; if it is positive, safe conditions are implied. A 0.5 performance function may be based on a familiar equation .5 0 from classical geotechnical analysis or, if no convenient function exists, it may be generated numerically using curve -.05 fitting. Normalized ln ( tan ϕʹ) -1 -1.5 FS=1.0  The performance function for a bearing capacity analysis -2 in which a strip footing is subjected to an allowable bearing -2 -1.5 -1 -0.5 0 .05 1 1.5 2

pressure (qall) might be written as: Normalized lnCʹ

g = FS – 1

Geo-Strata l geoinstitute.org 17 FORM is essentially an optimization method that Figures 3a and 3b show, respectively, typical failure iteratively fi nds the most likely values of the random mechanisms that might be displayed in two-dimensional variables that would result in failure. In Figure 2b, this (2D) and three-dimensional (3D) slopes modeled by is given by the contour ß = 0.6982 that just touches the RFEM. The 2D case represents a tailings dam with different performance function. The reliability index is easily random materials in the embankment and the foundation. converted to a probability of failure through standard Two different mechanisms have formed simultaneously cumulative distribution tables. In this case, ß = 0.6982 through the weaker soil formations, indicating a tendency corresponds to pf = 0.243. for rotational and horizontal sliding mechanisms. The 3D case is of a long dam or levee in which spatial correlation Random Finite Element Method (RFEM). This method effects have led to a concentration of weaker soils at a was developed by the authors in the early 1990s and particular location resulting in a localized failure zone. The involves a combination of fi nite element and random fi eld pf predicted by a RFEM is simply the number of simulations methodologies with Monte-Carlo simulations. The method that fail divided by the total number of Monte-Carlo is more computationally intensive than FORM but properly simulations performed. accounts for spatial variability and correlation, which recognizes that at any given site, soil properties are more The Road to RAGE likely to have similar properties if they are located close together rather than far apart. In particular, in addition to Although probabilistic concepts have been utilized by the means and standard deviations of input parameters (as geotechnical engineering for many years, they have tended required by FORM), RFEM also requires input of the spatial to be confi ned to “high tech” projects such as offshore correlation length, defi ned as the distance over which and where a statistical treatment properties tend to be positively correlated. Anisotropic of loading (e.g., the 100-year event) was an essential spatial correlation lengths can also be considered where the consideration. Nowadays, engineers are increasingly horizontal spatial correlation length may be longer than in required to explicitly consider risk and reliability in more the vertical direction. conventional investigations such as slopes and foundations. Detailed probabilistic analysis of two different earth slopes An advantage of RFEM, which becomes especially clear might conclude that the slope with the higher factor of in the study of the collapse of soil masses, is its ability to safety also has a higher probability of failure than the slope realistically allow the failure mechanism to “seek out” the with the lower factor of safety! Only a probabilistic method most critical and weakest path through the soil mass. This could reveal such a counter-intuitive outcome. can lead to quite convoluted failure mechanisms that are signifi cantly different to the classical mechanisms that occur The increased use of reliability-based design in in homogeneous soils. More importantly, the “seeking geotechnical engineering is also an incentive for a greater out” phenomenon, not easily accounted for by methods awareness of probabilistic methods. These methods feed such as FORM, generally gives lower factors of safety and directly into the choice of load and resistance factors higher pf values than would be predicted by traditional, but needed to achieve a target reliability level. “incorrect,” mechanisms.

Figure 3. Typical RFEM simulations of slopes showing failure mechanisms “seeking out” paths through the weakest soils. a) 2D simulation of a tailings dam showing the development of two different failure mechanisms. b) 3D simulation of a long dam or levee showing a localized failure mechanism due to a zone of weaker soil.

18 Geo-Strata l geoinstitute.org

Risk-based methodologies are here to stay because Commentary: they offer a more scientific and informative approach to assessing the reliability of geotechnical designs. Continued from page 14 Geotechnical engineers should become familiar with these concepts and include some of them in their routine given these challenges, how can geotechnical engineers get “toolbox” for geotechnical analysis. value from these developments in analysis and modeling? One approach is for academics and researchers to produce relatively simple and efficient tools and guidelines that can D. V. Griffiths, Ph.D., P.E., F.ASCE, is professor of Civil be used for routine practice based on the results of high- Engineering at the Colorado School of Mines in Golden, level analyses that are properly validated with high-quality CO. Professor Griffiths’ research interests include numerical experimental data. This may very well be the path that the and probabilistic methods in geotechnical engineering. He discipline will follow. We already see such trends developing offers regular ASCE Continuing Education short courses for among leading engineering firms and researchers. How fast geotechnical engineers on these topics. He can be reached at: this or similar approaches take root will depend on those in d.v.griffi[email protected] the practicing community who are open to embracing new developments, on university professors who will take the Gordon A. Fenton, Ph.D., P.Eng., M.ASCE, is professor lead in producing and teaching the new methods and tools, in the Departments of Civil Engineering and Engineering and on economics, which is the final arbiter as to the value Mathematics at Dalhousie University in Halifax, Nova of how we use our time and talents for technical activities Scotia, Canada. Dr. Fenton’s research interests include the going forward. development of reliability-based geotechnical design provisions and probabilistic modeling of geotechnical problems. He joins Dr. We believe that the new knowledge that has developed Griffiths in the offering of short courses on these topics. He can in the last 67 years, and particularly in the last 30 years, be reached at: [email protected] has tremendous value to the profession and can be used to even greater advantage. In fact, that is the major premise for GeoFlorida 2010. The conference’s technical program will provide a unique opportunity for engineers to see the forefront of modern analyses and numerical modeling methods and to share their own experiences and thoughts regarding further development of these methods to Contracting Services benefit the future of the discipline.

Rodrigo Salgado, Ph.D., P.E., M.ASCE, is professor of Civil Engineering at Purdue University in West Lafayette, In. Rodrigo is also technical program chair of GeoFlorida 2010. He can be contacted at [email protected]

Patrick J. Fox, Ph.D., P.E., M.ASCE, is professor at the University of California – San Diego. Patrick is also conference chair for GeoFlorida 2010. He can be contacted at [email protected]

Geo-Strata is interested in hearing from you. Please send your comments on this commentary to cetco.com/ccs 800.527.9948 [email protected].

20 Geo-Strata l geoinstitute.org Confessions of a Young Luddite

By Mary C. Nodine, P.E.

If I could live in a different time But despite my nostalgia, I always find Of engineering history than mine, My desk planted firmly in 2009 I’d choose, say, 1965, With two monitors, mouse and Bluetooth keyboard When drafting tables and compasses thrived And the latest version of Microsoft Word. On desks adorned with calc pads and ink, My abilities, too, live in present day Rather than laptop computers, I think. Thanks to classes in CAD and VBA. With only a slide rule, I’d have no clue For in those simpler, carefree days How to calculate two plus two. One could focus on the way But I admit that I love a well-thought-out To calculate a safety factor spreadsheet Uninterrupted by such matters That corrects in a second what I’d erase in a week. As slow networks and missing cables, And finding a critical circle is fun The proper font styles for titles and labels, With a stability program that takes seconds to run. Windows, menus, commands and cells, Popup email cries for help Perhaps I speak with so much heart And backing up her files, lest Of an era of which I was never a part She’s cursed with the Blue Screen of Death! To quell my perceived inadequacy At manipulating Civil 3D Yes, I think I’d like an office life Or worse, my utter lack of finesse Void of technologic strife, With a dead hard drive – but I digress. For old-school gadgets, tried and true We’re here, it’s now, the bar’s been raised. Have always been my favorite tools. A seepage analysis no longer takes days Fancy computer programs pale And I certainly count myself lucky indeed When compared to my trusty engineer’s scale. That edits to plans can be made with such speed. My poor heart sinks a bit for sure On days it never leaves my drawer. Still, the best of times at work, to me, With it I measure any span, Are when vellum graph paper features prominently Shrink a drawing and sketch a plan - Alongside my compass, triangle and scale, But it’s not a straightedge! Oh, the horror! Colored pencils to distinguish siltstone from shale. That’s what triangles are for. For soil’s not perfect and computers are nice, But sometimes it’s best to be not-so-precise. It’s not just scales on which I’m hooked, I’ll visit my clay, contemplate it at length, But maps and plans and old bound books. Find the back of an envelope to calculate strength. To huddle in the library, Then refreshed, I return to my laptop again, Study yellowed topography An answer already sketched out in my brain. And determine which formation Underlies my planned foundation Is sheer bliss. The hours fly by, it seems Mary C. Nodine, P.E., is a geotechnical poet Far from the glare of my monitor screen. and a project engineer with GEI Consultants, Inc. in Boulder, CO. She can be reached at: [email protected]

Geo-Strata l geoinstitute.org 21 Using Inversion to Improve Prediction in Geoenvironmental Engineering

By Craig H. Benson, Ph.D., P.E., D.GE, F.ASCE and Ronald J. Breitmeyer

T he processing capability available on today’s mean square error). Automated algorithms for conducting desktop computers has revolutionized how problems are inversions exist in many OTS software packages. The approached in geoenvironmental engineering. Complex outcomes from inversion can also be used to assess the non-linear problems can now be tackled using off-the-shelf conceptual model. (OTS) software equipped with graphical user interfaces (GUIs) that make model defi nition, data input, and visualization of output extremely simple and convenient. Some very sophisticated OTS software is available at no cost. For example, the widely used HYDRUS1D code can be downloaded from the internet (www.pcprogress.com).

This software will simulate complex non-linear coupled unsaturated water fl ow, heat transfer, and contaminant transport in one dimension (1D) using the fi nite element method. The code can also simulate geochemical processes, colloidal transport, and soil-atmosphere interactions. Perhaps most signifi cant is the very fast processing associated with the numerical methods and the convenient input and rapid examination of output afforded by the GUIs.

The output from today’s models can appear very realistic. In fact, the output can appear so realistic that the predictions may be confused with actual data. However, predictions are not reality, and comparisons with fi eld data have shown that deviations from fi eld conditions can be substantial. Two factors having great impact on the realism of the simulations are the conceptualization of the model and the material properties used as input.

If fi eld data are available, inversion can be used as Figure 1. Schematic of lysimeter a powerful tool to select appropriate input parameters. Inversion consists of running a model “in reverse” to fi nd the set of input parameters that results in the prediction that most closely resembles the state or behavior observed Inversion Example in the fi eld. An inverse simulation generally consists of a series of conventional (“forward”) simulations where the Inversion was used to determine appropriate hydraulic input parameters are varied systematically over defi ned properties and to identify shortcomings in a conceptual ranges. Predictions from the forward simulations are model used to simulate variably saturated fl ow for design compared with the fi eld data to identify the parameter of leachate recirculation systems for municipal solid waste set that provides the optimal fi t to the data (e.g., smallest (MSW) landfi lls. Field data for the inversion were obtained

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822 Bay Star Blvd., Webster, TX 77598 www.avantigrout.com phone. 800 . 877 . 2570 fax. 281 . 486 . 7300 from a large lysimeter (8.2 m tall and 2.4 m diameter) constructed at a MSW landfill in southern Wisconsin. The lysimeter was filled with MSW and instrumented with a variety of sensors, including time domain reflectometry probes to monitor and a dosing basin to record outflow. Waste within the lysimeter was separated into three layers and the hydraulic properties within each layer were assumed to be homogeneous and isotropic (construction records indicated that the MSW density within a given layer was reasonably uniform). A schematic showing the instrument locations in the lysimeter nest is presented in Figure 1.

The lysimeter is dosed periodically by applying approximately 1,800 L of leachate on the surface of the lysimeter over a 15-minute period. A two-dimensional model with radial symmetry was constructed in HYDRUS to simulate flow in the lysimeter in response to leachate dosing. Van Genuchten’s function was used to describe the water retention curve (WRC) and the Van Genuchten- Mualem function was used to define the unsaturated . A variable flux boundary was applied at the surface to simulate the inflow of leachate from dosing. The base of the lysimeter was assigned a unit gradient boundary condition. Outflow from the lysimeter and water contents recorded in the waste were used as the data for the inversion. Figure 2. WRCs and unsaturated hydraulic conductivity mea- sured in the laboratory on MSW (top). Smooth lines are the Complimentary laboratory tests were conducted on van Genuchten function (WRCs) or the van Genuchten-Mualem samples of the MSW to determine the saturated hydraulic function (hydraulic conductivity) (bottom). conductivity, WRCs for wetting and drying, and the unsaturated hydraulic conductivity function. These tests were conducted on MSW from the lysimeter that had step outflow method. Examples of the WRCs and the been shredded to < 25 mm. Rigid-wall permeameters were unsaturated hydraulic conductivity functions measured in used to determine the saturated hydraulic conductivity the laboratory are shown in Figure 2. and large-scale hanging columns were used to determine WRCs. The unsaturated hydraulic conductivity function Hydraulic properties obtained from the laboratory tests was determined from the WRC data using the multi- and from inversion are summarized in Table 1. Obtaining a

Table 1. Hydraulic Properties from the Laboratory and Obtained by the Inversion

Table 1. Hydraulic Properties from the Laboratory and Obtained by the Inversion

Laboratory-Measured Field Hydraulic Properties Hydraulic Properties Obtained by Inversion Density Sat. Sat. Layer (kN/m3) Hyd. α Hyd. α ℓ n ℓ n Cond. (kPa-1) Cond. (kPa-1) (m/s) (m/s) 1 11.2 3.1×10-9 – 8 1.3 0.5 2.0×10-5 1.53 1.3 0.5 2 8.2 2.3×10-7 – 5 1.3 1.8 5.8×10-5 1.58 1.3 0.2 3 7.8 5.0×10-7 – 5 1.3 1.9 7.3×10-4 0.24 1.3 1.8

24 Geo-Strata l geoinstitute.org reliable match between the model predictions and the field data requires saturated hydraulic conductivities much Figure 3. Measured higher than those measured in the laboratory (the saturated and predicted hydraulic conductivities obtained by inversion range from water contents two to nearly four orders of magnitude larger than those and cumulative measured in the laboratory). The pore interaction terms outflow (top). obtained by inversion (ℓ = 0.24 to 1.53) are also very Predictions made using hydraulic different from those measured in the laboratory (ℓ = -5 properties to -8). In contrast, the WRC parameters α and n obtained measured in by inversion are comparable to those measured in the the laboratory laboratory. and obtained by inversion (bottom). Deficiency in Conceptual Model

Comparisons between predicted and measured water contents and outflow from the lysimeter are shown in Figure 3. These predictions were made with the laboratory- measured hydraulic properties and with the properties obtained via inversion. Cumulative outflow from the lysimeter predicted with the inverted parameters matches the measured outflow reasonably well, although the predicted outflow is slightly lower than the measured outflow towards the end of the record. In contrast, the prediction using laboratory-measured parameters

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Geo-Strata l geoinstitute.org 25 than actually occurs in the fi eld.

The water contents predicted using the laboratory- measured hydraulic properties as input also provide a clue that the conceptual model has defi ciencies. The predicted rise in water content after dosing lags behind the rise observed in the fi eld. After the rise, however, the predicted water content remains essentially constant in the same manner that occurs in the fi eld. That is, the initial transient behavior is predicted more accurately using the inverted parameters, whereas the equilibrium condition is predicted more accurately with the laboratory-measured parameters. Inversion consists of running a model “in reverse” to find the set of input parameters that results in the predic- tion that most closely resembles the state or behavior observed in the field.

This inconsistency suggests that fl ow in the MSW could be better represented by a two-component fl ow fi eld consisting of preferential fl ow paths that transmit leachate in and out of the lysimeter rapidly and a matrix of less conductive MSW that retains water after dosing. The reasonable agreement between the equilibrium water contents observed in the fi eld and the water contents predicted using the laboratory-measured hydraulic properties suggests that the matrix was characterized reasonably well by the laboratory tests on the shredded MSW. However, even though large-scale tests were conducted, the tests probably were too small to incorporate preferential fl ow paths similar to those present in the lysimeter. The reasonable agreement between the inverted and laboratory-measured WRC parameters also indicates Figure 4. Predicted MSW saturation adjacent to leachate recircu- that the laboratory tests provided a reasonable assessment lation (blue rectangles) for saturated hydraulic conduc- tivities of 10-5, 10 -6, and 10-7 m/s. of conditions within the matrix. underestimates the measured outfl ow appreciably. The Practical Implications water content predictions are also more accurate when the An example of the practical signifi cance of the improved inverted hydraulic properties are used as input. The rapid parameterization obtained from inversion is illustrated rise in water content after dosing is captured, as is the in Figure 4, which shows predictions of MSW saturation subsequent leveling off, when the inverted parameters are surrounding four leachate injection trenches (blue boxes). used as input. The predictions were made with HYDRUS using WRC parameters obtained from inversion and three different The comparison of predicted and measured water saturated hydraulic conductivities ranging from 10-5 contents illustrates that the conceptual model of the m/s (comparable to saturated hydraulic conductivities lysimeter has defi ciencies. The fi eld data indicate that the obtained by inversion) to 10-7 m/s (comparable to saturated water content remains relatively constant after dosing, hydraulic conductivities measured in the laboratory). whereas drain down is predicted after dosing when the inverted parameters are used as input. Apparently, the high Very different distributions of saturation are predicted saturated hydraulic conductivity used to provide a good as the saturated hydraulic conductivity is varied. The MSW match with the outfl ow curves and the rapid rise in water with high saturated hydraulic conductivity is approximately content also predicts that the MSW will drain more readily 60 percent saturated by leachate injection, whereas the

26 Geo-Strata l geoinstitute.org Engineers need to scrutinize predictions The carefully, and avoid smart, green, easy way to being caught in the “model is reality” trap. Reduce Project Costs. predictions with lower saturated Choose economical and sustainable solutions hydraulic conductivity indicate the for soil stabilization challenges and MSW is 80-90 percent saturated. If the recirculation trenches were stormwater needs. operated based on findings from Experience value, quality, and predictions based on the laboratory- exceptional service: measured properties, the injection Genuine • Free project analysis & preliminary design rate might be too low to achieve ® • Installation & on-site project support moisture conditions that are optimal GEOWEB • The industry’s highest warranty for decomposition of the MSW. 800-548-3424 / 920-738-1328 These findings, and others, [email protected] illustrate that numerical models www.prestogeo.com can be powerful tools for prediction Made in the U.S.A. in geoenvironmental engineering. However, they may also produce predictions that appear realistic but are also unreasonable. Engineers need to scrutinize predictions carefully, and avoid being caught in the “model is reality” trap. Educators also need to train students about the pitfalls of model predictions, and the importance of “reality checks” and ground-truthing with field data.

Most predictions are very sensitive to how the model is conceptualized and parameterized. If field data are available, inversion can be used as a powerful tool to improve parameterization and to identify PRESTO potential deficiencies in conceptual GLOBAL LEADER • GLOBAL PARTNER models. While inversion may have AP-6146 30 years of innovation been cumbersome historically, many commercial software packages now include automated inversion routines. Engineers are encouraged Engineering at the University of Ronald J. Breitmeyer is a Ph.D. to explore using inversion to Wisconsin-Madison in Madison, WI. candidate and graduate research improve the quality and reliability of His research interests are primarily assistant in Geological Engineering at predictions. in designing, analyzing, and testing the University of Wisconsin-Madison in geotechnical components of landfills Madison, WI. He can be contacted at Craig H. Benson, Ph.D., P.E., D.GE, and other waste containment structures. [email protected] F.ASCE, is Wisconsin Distinguished Craig can be contacted at chbenson@ Professor and Chair of Geological wisc.edu

Geo-Strata l geoinstitute.org 27 Using Numerical Analysis in Geotechnical Engineering Practice

By Lidija Zdravković, Ph.D., DIC and David M. Potts, Ph.D., DSc, FREng

N umerical analysis, in terms of fi nite element or fi nite If no other model input parameter is required, this difference methods, has become a popular calculation implies that the model is assumed to be associated, tool in geotechnical design. It is particularly necessary to meaning that the direction of plastic strains can be apply numerical analysis in cases of complex geotechnical determined from the model’s yield surface, which is defi ned structures and ground conditions, where classical methods by c’ and φ’. It further implies that the angle of dilation in of analysis (linear elastic, limit equilibrium, stress fi eld, and the soil, ψ, is equal to φ’. limit analysis methods) cannot produce adequate solutions. As a result, the model will produce excessive dilative A number of specialist geotechnical software packages (expansive) strains in the soil. In addition, it will not be are currently available commercially and in research. They possible with such analysis to determine the ultimate load usually differ in the level of sophistication and in the way for volumetrically confi ned problems, such as an undrained in which constitutive models, boundary conditions, and bearing capacity of a , or a capacity of numerical solvers are implemented, as there is currently no a pile foundation. This outcome is illustrated in Figure 1, internationally agreed guidance on best practice for such where drained load-displacement curves for a vertically implementations. Consequently, it is not unusual to obtain loaded pile 1.0 m in diameter and 20 m long are presented, different answers to the same problem from different in a soil with c’ = 0 and φ’ = 25°. software. For a successful analysis, it is also important for the user to understand how the applied software works and what might be going on in the computer “black box.”

The linear elastic-plastic Mohr-Coulomb model, one of the simplest geotechnical constitutive models, provides a good example of the some of the problems and solutions involved. This model is a feature of most geotechnical software, but users still make mistakes due to their lack of understanding of the model. Analyses described in the following sections were performed using the Imperial College fi nite element program ICFEP.

Ultimate Limit States

A common design requirement for geotechnical structures is the bearing capacity of foundations, both shallow and deep. If the Mohr-Coulomb model is applied in such analysis, the following model input parameters are For the case of an associated Mohr-Coulomb model, required: the load-displacement curve never reaches a limit load, no matter how far the pile is pushed into the ground. • for elastic soil behaviour: soil stiffness in terms of Faced with such a prediction, the user may then arbitrarily the Young’s modulus, E, and Poisson’s ratio, ν; determine the limit load, for example, as the magnitude and of the vertical force when the displacement is equal to 10 percent of the pile diameter (0.1 m in this case). This • for plastic (failure) behaviour: the soil , arbitrary decision is non-conservative, as soil dilation is c’, and the angle of shearing resistance, φ’. normally smaller than φ’.

28 Geo-Strata l geoinstitute.org VisualFEA - Geotechnical Finite Element Analysis Program Advanced modeling and analysis

Capability of looking inside the solution

Failure envelope

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Stress sampling

Stress path Mohr's circle

Variety of applications

Seepage analysis Frame analysis (3D rendering of the phreatic surface) (coupled with seepage analysis) (with specified sections)

Website : www.visualfea.com Phone : United States (206)923-9824 Email : [email protected] United Kingdom (020)3287-9825 If the software has the flexibility for the user to input the angle of dilation to be smaller than φ’, then for any value of 0 < ψ < φ’, the analysis will still not produce an ultimate limit load, as shown in Figure 1 for the case of ψ = ⅔ φ’. The user will again have to make an arbitrary decision on the magnitude of the limit load. Only if ψ = 0 will the load-displacement curve reach an ultimate load, as shown in Figure 1. Such an ultimate load will be conservative, as most soils normally dilate to some extent, but the outcome will at least be the theoretically correct ultimate load (for ψ = 0), without any arbitrary decision from the user.

It is not unusual to obtain different Figure 2. Layout of Jubilee Line tunnels at St. James’s park. answers to the same problem from the model dominate the predicted behaviour. If a simple, different software. linear elastic-plastic Mohr-Coulomb model is applied, such as used in the pile loading example, the predicted surface settlement trough is shown in Figure 3. In this case, Serviceability Limit States the pre-failure behaviour of the Mohr-Coulomb model is characterised by an isotropic, linear elastic Young’s Apart from failure conditions, it is also necessary to modulus, which increases linearly with depth, producing design geotechnical structures for working conditions, the surface settlement trough which does not resemble the where ground deformations are limited so that the new measurements. and the existing structures and services can function adequately. This is particularly important for designs in A possible advancement in modelling the pre-failure urban environments, where, for example, deep excavations, behaviour of the soil could be the introduction of tunnels, and new foundations have to be constructed anisotropic linear elastic stiffness characteristics. In the next to, or underneath, existing structures and services. case of London Clay, which is a heavily overconsolidated What becomes important for design is the determination material, the stiffness in the horizontal direction is of ground movements imposed by new construction and much higher than that in the vertical direction. If these whether they can cause any damage to existing buildings. characteristics are introduced in the pre-failure behaviour of the Mohr-Coulomb model, with both directional stiffnesses Figure 2 shows the layout of two London Underground increasing linearly with depth, the predicted surface (LU) tunnels as they pass into St. James’s park in London, settlement trough (Figure 3) is slightly better than that of UK. The 30-m-deep westbound and the 20-m-deep the isotropic linear elastic pre-failure model, but is still too eastbound tunnels, of 3 km total length, are part of the shallow and wide compared to the measurements. extension of the LU Jubilee Line, and were constructed between 1994 and 1996. The figure shows that at this Advancements in laboratory testing over the past 20 location the tunnels pass directly underneath the Treasury years, in particular the introduction of local instrumenta- building, with several other buildings (shaded areas) in tion on triaxial samples, have shown that soil stiffness is the direct vicinity. To the left of the Treasury building, the not constant, i.e. linear elastic. Rather, it is highly nonlinear, tunnels pass underneath the greenfield area of St. James’s park, which was heavily instrumented for monitoring of both ground movements and stress changes in the soil due to the tunnels’ advancement. Pre-Failure Model Figure 3. Predicted and measure surface settlement trough above the westbound tunnel.

Both tunnels were excavated undrained in the London Distance from centre line (m) Legend Clay formation. The measured settlement trough above centre line 25 50 0 the westbound tunnel at St. James’s park, which was isotropic linear elastic constructed first, is used to demonstrate the necessity for advancing the capabilities of a constitutive model in order anisotropic linear elastic to obtain reasonable predictions of tunnel-induced ground nonlinear elastic Settlement (mm) 20 movements. fi eld data

Since in this type of boundary value problem the deformations are small, the pre-failure characteristics of

30 Geo-Strata l geoinstitute.org varying from a high value at very small strains to a small value at intermediate to large strains. Soil stiffness also de- pends on the stress level in the soil such that it increases Figure 4. Shear stiffness degradation of London clay. G with an increasing stress. sec p′ Shear Stiffness Apart from failure conditions, it is 600 nonlinear elastic 400 also necessary to design geotechnical CAU compression test 200 structures for working conditions, CAU extension test 0 where ground deformations are limited 0.001 0.01 0.1 1.0 so that the new and the existing Shear strain (%) structures and services can function adequately. from Figure 3 that such modelling significantly improves the prediction of the surface settlement trough above the tunnel. An example of how the shear stiffness, G, of London Clay, normalised by the mean p’, varies with strain level in both triaxial compression and extension is Pitfalls of Simple Models shown in Figure 4. The figure clearly shows that stiffness degradation is highly nonlinear and therefore must be The complexity of the constitutive model required in modelled using a nonlinear elastic model. If such a model a finite element analysis depends on the nature of the is introduced to represent the pre-failure behaviour of the boundary value problem to be analysed. The simple, but Mohr-Coulomb model and applied in the analysis of the extensively used, Mohr-Coulomb model has shortcomings. westbound tunnel construction at St. James’s park, it is clear For ultimate limit state problems such as bearing capacity

32 Geo-Strata l geoinstitute.org in soil, the Mohr-Coulomb model produces excessive dilative strains and cannot provide an ultimate load BOLD. POWERFUL. For the GEOTECHNICAL INDUSTRY for volumetrically confined problems when dilation in the model is greater ® than zero. 8040DT Geoprobe Machine For serviceability limit state problems where ground movements are limited, deformations do not realistically match observed behaviour if the Mohr-Coulomb model is characterised by an isotropic, linear elastic Young’s modulus. Where these limitations are unacceptable, such as for more complicated structures and ground conditions, more advanced constitutive models may be needed. These models may have to deal with variable soil permeability, soil structure, creep, unsaturated soil behaviour, or strength anisotropy. The classes of models that can simulate these aspects of soil behaviour are known as the kinematic surface and If you’re looking for a machine that has unmatched capabilities, bounding surface plasticity models. is big on power and performance, and makes high value holes, then you’re looking in the right direction! Additional pitfalls can occur when selecting appropriate boundary conditions for a particular 8040DT MACHINE APPLICATIONS problem. The standard static and • Cordless CPT • Seismic CPT hydraulic boundary conditions that • Standard Penetration Testing (SPT) are commonly available may be • Monitoring Well Installation • High-capacity Augering inadequate and misleading, especially • Electrical Conductivity Logging • MIP Logging if the problem has to consider • Large diameter casing advancement infiltration, evapo-transpiration, or dynamic loading conditions.

Lidija Zdravković, Ph.D., DIC, is an associate professor at Imperial College London. Her main research interests are in the field of numerical www.geoprobe.com geotechnical analysis, involving both 1-800-436-7762 software development and engineering applications. She has co-authored two books on geotechnical finite element analysis with David Potts. She can be reached at l.zdravkovic@imperial. London. He has worked extensively on ac.uk the development of computer methods Geo-Strata is interested in of analysis and their application to the hearing from you. Please send David M. Potts, Ph.D., DSc, FREng, design of real geotechnical structures. your comments on this article is a professor and the deputy head of the He is the author of the geotechnical to [email protected]. Department of Civil and Environmental software ICFEP. He can be reached at Engineering at Imperial College [email protected]

Geo-Strata l geoinstitute.org 33 Recently Published Books from

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E xperts predict that an extreme weather event in modeling and analysis tools for both short and long- Sacramento’s Natomas Basin has the potential to produce term scenarios, demonstrated innovative probabilistic flood waters in excess of 20 ft deep, which would affect vulnerability studies to quantify relative reliability of more than 53,000 acres and more than 70,000 people. embankments, and developed ever more accurate and The U.S. Army Corps of Engineers (USACE) Sacramento efficient answers to highly complex questions. District has stated that the 42 miles of levees that contain the Natomas Basin do not provide a 100-year level of Sacramento River Options flood protection. Subsequently, the Federal Emergency Management Agency (FEMA) new flood zone maps, The NLIP site footprint includes 700 parcels of land effective in December 2008, led to flood insurance around the perimeter of the basin. The flood protection requirements for existing residents and a de-facto system is composed of several major components: moratorium on issuance of new building permits in the area. • Sacramento River East Levee (approx. 18 miles),

• Natomas Cross Canal South Levee The goal of the NLIP is to provide 100- (approx. five miles), year protection as quickly as possible • American River North Levee (approx. two miles), and and 200-year protection for all levees • Natomas East Main Drainage Canal West Levee by 2013. (approx. 13 miles) with the Pleasant Grove Creek Canal West Levee (approx. three miles). In response, the Sacramento Area Flood Control Agency (SAFCA) initiated the Natomas Levee Improvement Program (NLIP), a $618 million, seven-year project to The Sacramento River is the main expedite repair and rehabilitation of the entire levee system. drainage feature of the northern The goal of the NLIP is to provide 100-year protection as quickly as possible (with a target of 50 percent of the levees part of the region, flowing generally improved by 2011), and 200-year protection for all levees southward from the Klamath by 2013. Mountains to its discharge point into SAFCA is looking to a team of expert geo-professionals Suisun Bay in the San Francisco Bay to develop an understanding of the complexities of this unique levee system and engineer the necessary Area. improvements. In the wake of Hurricane Katrina, the standard of care for the nation’s levees has been redefined For the Sacramento River portion of the project, since 2005, as have the methodologies, tools, and the geotechnical evaluation team opted to run three techniques for analysis and design. slope stability solutions in parallel to see if results came within the acceptable algorithmic differentials. As The project provides a unique opportunity to further background, engineers found that the available slope advance the state of the geotechnical practice in terms of stability analysis tools used to assess the New Orleans levee analysis and design. Three years into the program, the levees provided inconsistent answers when assessing the engineering team has performed side-by-side comparisons same problem. The slope stability tools selected included of the most advanced groundwater and slope stability the industry benchmark system, UTEXAS4 developed by

36 Geo-Strata l geoinstitute.org point into Suisun Bay in the San Francisco Bay Area. In the project area, the river is confined by man-made levees that were generally constructed on Holocene-age alluvial and fluvial sediments deposited by the current and historical Sacramento and San Joaquin Rivers and their tributaries. Pleistocene deposits underlie the Holocene deposits.

The of the region does not lend itself to regular spaced borings, but required a detailed exploration program that incorporated helicopter electromagnetic surveys (HEM) and electrical resistivity testing to assist in identifying crevasse splay deposits and other anomalies that could lead to seepage and stability issues. In addition, piezocone penetrometer (CPT) and vane shear (VST) testing was used to evaluate areas of soft and clay.

Using the field data, the engineers first input the various parameters into the three slope stability analysis programs to evaluate the influence of each levee cross section’s soil shear strengths, pore water pressures, and loading from proposed remediation strategies on the factor of safety against failure. While not as graphically advanced or presentation friendly as compared to more recently developed solutions, the UTEXAS4 slope stability program uses limit equilibrium procedures to calculate a factor of safety against failure. Similar to the Figure 1. Outline of the Natomas Basin levees surrounding a portion of Sacramento, UTEXAS4 solution, SVSlope provides CA and areas to the north. advanced analysis of slope stability that can incorporate probabilistic methods including Monte Carlo, Dr. Stephen Wright at the University of Texas, SLOPE/W Latin Hypercube, and Alternate Point Estimation Method by Geo-Slope International, Ltd., and the newer SVSlope® sampling, as well as the industry-accepted Duncan, Wright, limit equilibrium slope stability solution from SoilVision and Wong rapid draw-down methodology. SLOPE/W is also Systems, Ltd. capable of sensitivity and probabilistic analysis.

One River, Many Variables The greatest analytical edge gained from recent software is in seepage analysis. Traditionally, engineers have relied The geotechnical team had to deal with a number of on programs like Seep2D to compute seepage on profile complexities. The Sacramento River is the main drainage models such as for earthen dam and levee cross sections. feature of the northern part of the region, flowing generally Many new industry professionals are not familiar with southward from the Klamath Mountains to its discharge the command words and the formatting required by the

Geo-Strata l geoinstitute.org 37 older DOS-based programs, which can make the overall process very laborious. For this effort, the engineering team also looked to SVFlux, a 1D, 2D, and 3D fi nite element groundwater modeling solution, and SEEP/W to provide the input to the slope stability programs. Both the SVFlux and the SEEP/W software solutions allow for import of information generated from their respective seepage programs into the slope stability programs.

One of the more useful features from the older DOS programs is the flex- ibility to select data from the seepage analysis results for use by importing pore pressures from specific layers and Figure 2. Example slurry stability analysis using SVSlope, using piezometric lines for others. one of three slope stability programs used.

One of the more useful features from the older DOS programs is the fl exibility to select data from the seepage feature from the older DOS programs was also found in the analysis results for use by importing pore pressures from SVFlux solution. Although not explicitly permitted by the specifi c layers and using piezometric lines for others. This design parameters of several levee regulatory agencies, both

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38 Geo-Strata l geoinstitute.org SVFlux and SEEP/W can provide transient analysis, which in behavior due to the distribution of material properties. can be used to evaluate the change in factor of safety with UTEXAS4 does not explicitly perform this type of analysis as changes in water level and evaluate the progression of the of yet, however SLOPE/W and SVSlope have this capability. wetting front through the levee cross section.

Probabilistic methods are also available in the seepage A critical advance in the evolution of software, which run several analyses while varying the water levels and variables such as the hydraulic conductivity and levee analysis and design is the ability anisotropy to see the change in gradient or uplift pressure. to perform probabilistic analysis, which The automation of these analyses greatly improves the engineer’s effi ciency, but the effi ciencies gained should not develops a probability distribution be squandered. The time savings should allow an engineer for a specific material property to more time to think about the implications of the results of the analyses and thereby develop a better understanding of see variations in behavior due to the the signifi cance of the results. distribution of material properties.

Thinking About Probability SLOPE/W solves for a deterministic failure surface and then performs a probabilistic analysis on that surface. The state of the practice in levee analysis and design SVSlope, on the other hand, can vary the failure surface as a has evolved considerably in the last four years. A critical function of material properties on the slip surface, e.g., the advance in this evolution is the ability to perform probabilistic analysis results in changes to the slip surface probabilistic analysis, which develops a probability location. Currently, the probabilistic analysis evaluations distribution for a specifi c material property to see variations are made for internal use, calibrating on probability of

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Geo-Strata l geoinstitute.org 39 failure. Regulatory agencies have guidance on the use of risk (Reach 2-4B) project. This work is slated to be completed and reliability analysis of levees; however, the agencies seem in 2010. Sacramento River Phases 2 and 3 are expected to be reluctant to use them due to a lack of calibration of, to begin construction in 2010. The construction on the and thus acceptance by the general engineering community, improvements is scheduled for a completion of around to the “probability of failure” concept. Most engineers 2015; however the bulk of the analysis is anticipated to be have been indoctrinated using the factor of safety and have finished by early 2010. developed “internal” calibrations. They have a “feel” for what a 1.4 factor of safety is like. They don’t have a “feel” Of course, no matter how good the software is in for an annualized failure rate of 1/30. performing the analysis, the most critical step is the wise selection of parameters that go into the analysis software. With today’s advanced solutions, engineers can readily see NLIP Update the impact of varying those parameters on critical levee structures during ordinary and extreme conditions. It is Using these analysis techniques, the geotechnical design imperative that no matter how advanced the software is, it team has been able to contribute to overall levee repair cannot and should not replace sound engineering judgment designs that are also moving through the construction and an appreciation of the physics of the problem. phase. The first of the NLIP construction projects began in 2007, with additional work in 2008. Major improvements Scott Anderson, P.E., M.ASCE, is a principal engineer, began in spring 2009, and additional phases have been Numerical Modeling Group Director, with Kleinfelder, Inc. in awarded. In August 2009, groundbreaking took place on the Sacramento, CA. He specializes in numerical modeling and $22 million Natomas Cross Canal Phase 2 and Sacramento advanced laboratory testing, and serves on the Computational River East Levee Phase 1 (Reach 1) improvements and a Geotechnics Committee of the Geo-Institute. Scott can be reached second $21 million Sacramento River East Levee Phase 1B at [email protected] Geo-Strata is interested in hearing from you. Please send your comments on this article to [email protected].

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CO2 Sequestration: Fractures Are Enabling Clean Energy Options

By Joseph Morris, Ph.D., and Laura Pyrak-Nolte, Ph.D.

Figure 1. The amine CO2 removal facilities at Krechba. (Image courtesy of ISG CO2 JIP)

F or most people, the idea that rock fractures can “go In Salah Gas green” might seem a bit far-fetched. However, large-scale carbon capture and sequestration (CCS) projects involving The In Salah Gas (ISG) CO2 Storage project in Algeria is one example of what will ultimately be many projects annual injections of millions of tons of CO2 into geologic formations deep underground have emerged as a method to needed to achieve significant reductions in greenhouse enable substantial reductions in greenhouse gas emissions. gas emissions. The ISG injects approximately one million

tons of CO2 annually into a deep saline formation. The Subsurface injection projects will need to be employed response of the formation illustrates how fractures act to on a grand scale if geological carbon sequestration is to amplify the connection between geochemical and hydro- affect significant reductions in greenhouse gases in the mechanical processes in subsurface reservoirs. Though other atmosphere. These projects will likely require multiple injection projects will involve distinct geological formations and structural features from those of the In Salah project, into which millions of tons of CO2 will be injected over 30 years or more. For storage in saline formations, this is likely many geologic targets will contain pre-existing fractures to create large and increasing pressure perturbations that and faults. In addition, potential pressure perturbations will grow over the duration of the injection project. within the formations from the large rates and volumes of injection can activate existing fractures and faults, and/or Each project will involve distinct geological features and create new fractures within the reservoir or caprock. many will include geologic targets containing preexisting fractures. In addition, the large rate and volume of injection In Salah Gas has two fundamental goals: (1) 25-30 may induce pressure perturbations within the formation years of 9 billion cubic ft/year of natural gas production that can activate existing fractures and faults, or create new from eight fields in the Algerian Central Sahara, and (2) fractures within the reservoir or caprock. Consequently, successful minimization of the associated environmental understanding the role of fractures in controlling flow impact by capture and subsurface isolation of excess CO2 through rock masses is key in predicting the performance of extracted from production streams. The gas produced from these fields is too rich in CO for export to Europe and is industrial-scale CO2 geological storage. 2 consequently purified before being piped out of the field

area. Separated CO2 is normally vented from gas plants,

42 Geo-Strata l geoinstitute.org Amine CO2 Removal

Figure 2. CO2 injection scenario employed at Krechba. If this image was to scale, the 20-m thick reservoir would appear as a single, almost fl at, line.

PROCESSING FACILITIES 

5 GAS 3 CO2  PRODUCTION INJECTION WELLS WELLS

Figure 1. The amine CO2 removal facilities at Krechba. (Image courtesy of ISG CO2 JIP) GAS

WATER

Image adapted from ISG CO2 JIP. but at In Salah, the separated CO2 is geologically stored in a deep saline formation that has been characterized to oil and gas standards. Since 2004, the ISG facility at Krechba,

has stored the CO2 in a deep saline formation, down-dip from the producing gas field (Figure 2). 1 Cretaceous Sandstone & Mudstones ~ 900 metres thick (Regional Aquifer) Hydro-Mechanical Effects

The Krechba reservoir is an approximately 20-m-thick sandstone unit at a depth of 1800 m, situated 150 km 2 Carboniferous Mudstones from the nearest settlement, In Salah. Predicting the hydro- ~ 950 metres thick mechanical response of the reservoir is proving to be important in understanding the ultimate fate of the injected

CO2. Although there is no evidence of faulting through the overlying caprock, there are faults and extensive fracture 3 Carboniferous networks within the reservoir itself that potentially control Reservoir ~ 20 metres thick the mobility of the CO2. Figure 3 shows the potential faults identified within the reservoir and some of the fractures identified from FMI (Formation MicroImager) logs. Recent hydro-mechanical analysis has demonstrated that features shown on the fault map are consistent with observation

of surface uplift and detection of CO2 by monitoring wells (Figure 4).

Additional analysis was performed to investigate defor- mation of the fracture network within the reservoir. Frac- tures that fail in shear are expected to develop enhanced

Geo-Strata l geoinstitute.org 43 Geochemical Effects

In addition to hydro-mechanical effects, injecting CO into a subsurface reservoir can initiate a complex Seismic Data 2 set of geochemical reactions that involve interactions Figure 3. Seismic data indicates between aqueous solutions and minerals in the host rock potential faults in the reservoir, but No potential faults not the caprock (at top). (Figure 6). Consequently, a complete assessment of a

Indications of predom- given reservoir’s suitability for CO2 sequestration requires inant fracture orienta- geochemical analysis in addition to geomechanical analysis. tions are shown on FMI For example, geochemical reactions can lead to mineral logs (at bottom). (Data courtesy precipitation in voids and fractures or dissolution of the of ISG CO2 JIP). host rock.

The hydro-mechanical behavior of fractures can be significantly affected by such geochemical interactions. For example, while dissolution along fracture surfaces may initially enlarge the apertures in a fracture, the subsequent changes in the stress distribution along the fracture plane can lead to closure or reductions in apertures that in turn reduce fluid flow through the fracture and fracture networks.

Potential faults Understanding the role of fractures in controlling flow through rock masses is key in predicting the performance of

industrial-scale CO2 geological storage.

permeability, resulting in modification of the CO plume. 2 Recent laboratory experiments have shown that Figure 5 shows the response of the combined fracture and preferential dissolution at points of contact between fault network to a hypothetical pore pressure increase under surfaces can lead to large displacements that rapidly different in-situ stress conditions. This calculation considers reduce fracture apertures. The amount and rate of closure the poroelastic response of the fractured rock mass and in- of a fracture subjected to dissolution depends on the cludes the redistribution of stresses through the combined spatial distribution of apertures within the fracture which fracture-fault network. The black regions highlight sections controls the hydrodynamic behavior and also on the spatial of the faults and fracture network that will fail and poten- distribution of local chemical reaction rates. On the other tially enhance permeability within the reservoir. In particu- hand, recent research performed at Purdue University has lar, there are two fault sections near the injection site that demonstrated that mineral precipitation within a fracture are predicted to be conduits for fast flow in this scenario. can lead to blocking or plugging of the fracture, thereby reducing storage capacity of a reservoir or potentially acting Uncertainty in the in-situ stress orientation, fracture as a mineral seal to trap CO in the subsurface. strike variability, and fault strike uncertainty/variability 2 was a key issue that was also explored. For example, it is an unfortunate fact that the in-situ stress state is only poorly The Future of CO2 Sequestration characterized for most fields. Consequently, the precise Understanding of CO2 sequestration performance is level of induced shear stress on fault segments will be moving forward on multiple fronts. In the laboratory, equally uncertain. For the fracture network at In Salah, even detailed experiments are providing insight into the linkage though the in-situ stress was well characterized, we found between geochemical and geomechanical processes at small the hydromechanical response was very sensitive to the scales. In the field, full-scale deployment at projects such orientation of the in situ stress. as the In Salah Gas Project are giving indications of how fracture networks respond to enhance both injectivity and storage capacity.

44 Geo-Strata l geoinstitute.org 8 Displacement 7 Remote Sensing Tools Rate 6 Figure 4. Geomechanical analysis of faults 5

showing expected fast fl ow paths (blue) and N29 ˚ 5 ΄ fl ow barriers (red). InSAR data (Courtesy of ISG 4 CO2 JIP) is a remote sensing tool to monitor 3 subsurface volume change (red = uplift; blue = 2 subsidence). 1 0 -1 mm/year -2

N

F12 predicted to be conducting

F9 predicted to be stable: Flow barrier south of KB-502

Impermeable

Permeable

SHmax

Discrete Element Simulations Figure 5. Discrete Element Simulations using the Livermore Distinct Element code for eXport explore sensitivity of pore-pressureDiscrete induced fracture Element network shear Simulations failure to uncertainty in in-situ stress orientation. Figure 5. Discrete Element Simulations using the Livermore Distinct Element code for eXport explore sensitivity of

Spore-pressure induced fracture15 network˚ shear failure to uncertainty in in-situ stress orientation.0˚ 15˚

Hmax SHmax SHmax

S 15˚ 0˚ 15˚

Hmax SHmax SHmax        N N

10 0.6 MPa 10 0.6 MPa 0 Fracture Network Fails in Shear 0.0 MPa

0 Fracture Network Fails in Shear 0.0 MPa

Geo-Strata l geoinstitute.org 45 Chemical and Hydromechanical Processes

Figure 6. Within the geologic sequestration target, chemical and hydromechanical processes are coupled (Johnson et al., 2003). Geo-Strata

Coming in March/April 2010: Levees At Risk

• Is Doing Levee Work Worth Destroying Your Firm?

• Making Levees Safer by Hedging Our Bets

• A Decade of Delivery: The Geo-Strata Story

• What’s In Your Levee? • Fast-Track Repairs of Critical Levee Erosion Sites

• Characterizing the Seismic Threat to California’s Water Supply

• Geotechnical Evaluation of Joseph Morris, Ph.D., is a research scientist at the Lawrence California Central Valley Urban Livermore National Laboratory in Livermore, CA, where he Levees

manages several CO2 sequestration-related research projects. He has also developed multiple software tools for simulating coupled • So You Live Behind a Levee! hydromechanical effects in fracture networks. He can be reached at [email protected] And, introducing a new feature: Laura Pyrak-Nolte, Ph.D., is professor of physics at Purdue University in West Lafayette, IN where she studies the effects of fractures on seismic and acoustic wave propagation, the geometry “Lessons Learned from Geo- of single fractures and fracture networks, and fl uid fl ow through Legends” fractures and fracture networks. She can be reached at ljpn@ physics.purdue.edu

46 Geo-Strata l geoinstitute.org ORGANIZATIONAL MEMBERS Anderson Drilling Ardaman & Associates, Inc. Brayman Construction Corporation CH2M Hill Con-Tech Systems, Ltd. Condon-Johnson & Associates, Inc. D’Appolonia DBM Contractors, Inc. DGI-Menard, Inc. ECS Limited Ellington Cross Fudo Construction, Inc. Fugro Consultants LP GRL Engineers/Pile Dynamics Gannett Fleming, Inc. Geocon Incorporated Geokon, Inc. Geopier Foundation Company Geo-Solutions, Inc. GeoStructures, Inc. Geosyntec Consultants Geotechnology, Inc. GEOTEKNIK AS Golder Associates Inc. Gregg Drilling & Testing, Inc. Hayes Drilling, Inc. Hayward Baker Inc. Insulfoam DBM Contractors, Inc. Kelly Tractor Co. Kleinfelder, Inc Donald B. Murphy Contractors, Inc. Layne GeoConstruction Loadtest, Inc. Geotechnical Design & Construction McKinney Drilling Company Moore and Taber Design/Build Moretrench Serving the Western U.S.A. NTH Consultants, Ltd. Earth Retention Nicholson Construction Company Rembco Geotechnical Contractors, Foundation Support Inc. Slope Stabilization Robert B. Balter Company S&ME Inc. Ground Improvement STS Consultants, Ltd. Dewatering Schnabel Engineering Schnabel Foundation Company Strata Systems Inc. Terracon, Inc. Terra Insurance Company Testing Service Corporation Thompson Engineering, Inc. URS Corporation ZETAS Zemin Teknolojisi A.S. Give your organization the G-I advantage. To join, go to www.geoinstitute.org. Click on Organizational Members. 800-562-8460 www.dbmcontractors.com

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By John Bachner

Legal professionals must be important; a lot of them charge $300-$350 an hour and more. And by applying that metric, one would have to conclude that geoprofessionals are far less important, because many of them charge so much less. But that conclusion would be wrong: Geoprofessionals are vital to preserving humankind’s sustainability on Earth, whereas attorneys…hmmmm: What do they do that makes their fees acceptable?

In fact, it’s not so much what attorneys do as what people perceive they do. And as we all know, what people perceive to be their reality is their reality. So why is it that people perceive what attorneys do as being so much more valuable than what geoprofessionals do? Because attorneys know, as you should, too, that the world is run by those who show up…and you cannot show up unless others notice you’re there. Sure, preserving our species is important. But look what happens when no one knows public-speaking performance. He asked me what he could you’re doing it. do to improve and I suggested that he get involved in Toastmasters International. He did and, about seven years Geoprofessionals have offered various explanations later, I was in his “neck of the woods” and gave him a call. for not showing up, telling me and others that they “Joining Toastmasters was the best thing I ever did,” he told cannot handle confrontation and the risk of rejection; me. “I learned how to get over my public-speaking fears and that they don’t like compromise; that they’re not “wired” inhibitions, and now I really enjoy it. In fact, I do it every for public display; and so on. And we can also look at the chance I get.” And the more he does it, the more chances he way geoprofessionals are educated, which – for the most gets to do it. part – involves an exclusive focus on technical issues, with little regard for history, English, art, public speaking, etc.… How important is that? It’s huge, frankly, because the educational staples of most lawyers. (I’ve been told speaking confi dently in public is how people know you’re it’s possible to go through four years of an engineering or there, showing up. It’s what leaders do. Do you want science program without saying a single word in class other society to think you’re important? Speak up! Do you want than “Present.”) to earn the kind of fees that important people command? Speak up! And be sure to do it via the organizations that “We need to change the way geoprofessionals are comprise the public. Does that mean geoprofessional educated,” a number of senior practitioners say. But not as groups, like G-I? As confi dence-building starts, sure; they many agree that almost an additional year of study is called comprise friendly enclaves of like-minded individuals for. And even fewer insist that geoprofessionals have more whose compatible backgrounds help novice speakers feel background in the humanities. So what does that mean? comfortable. But graduate as quickly as you can to public groups whose members’ common interest is something In truth, it means nothing at all. other than the same technological endeavors, so you can impress upon folks other than geoprofessionals what Well over 1,000 people have now gone through it is you and your cohorts really do. And that’s pretty ASFE’s Fundamentals of Professional Practice course for impressive stuff. After all, you help make human progress geoprofessional fi rms’ rising stars; six months of remote possible and, more and more, you are doing so while study followed by a course-concluding 2½-day seminar. helping society preserve Earth’s physical resources for use Speaking before small groups is an important element of by future generations. Should that make you feel good the seminar and, for many of the younger participants, about yourself? Absolutely. Should that give you the it’s the fi rst public-speaking experience of their careers. A wherewithal to stand up in front of people and address lot of them are not very good at it. One such participant – them a confi dent, persuasive manner? It’ll help, but you’ll let’s call him Steve – was particularly upset with his poor need more.

Geo-Strata l geoinstitute.org 49 First and foremost, you’ll need to stop believing in flimsy excuses. Being able to speak well in public is not a genetic endowment. It is an acquired skill you hone through practice. (If Steve can do it, trust me: You can do it.) And when you gain self-confidence as a speaker and combine it with your self-confidence as custodian of our planet, you have something powerful to offer.

How long will it take before people start to realize that geoprofessionals are not only important, but even more important than lawyers? I have no clue. But I do know that, unless you and your peers are willing to invest the time and energy required to be able to speak confidently in public, it’s never going to happen. Sure, lawyers may have an advantage by virtue of their education and by virtue of what some may say is a natural proclivity for humanistic involvement. But lawyers are not custodians of the planet. You are. And while many attorneys may be passionate about our environment and preserving it, passion doesn’t get the job done. Nor does a law degree or passing a bar exam. But people aren’t going to know that as long as geoprofessionals stay mum. And while you may agree with those sentiments, nodding one’s head does nothing to improve the situation. Geoprofessionals need to show up. That means you. You need to believe that what you do is important, because it is. And you need to believe that, as a result, you are important, because you are. And then you need to get out of your comfort zone and show up, then let others know you’re there. You can do that.

Speak up.

I Tiltmeters for monitoring structural stability. I The Vibrating Wire Advantage: › John P. Bachner is the executive I Strain Gages for monitoring geogrid strains. Excellent long-term stability, long › vice president of ASFE, a not-for-profit I for monitoring ground stability. cable lengths, accuracy and reliability › association that provides programs, I Load Cells for monitoring tiebacks and rock bolts. even in the most adverse conditions. › services, and materials that its members – geoprofessional firms – apply to

1 • 603 • 448 •1562 Geokon is achieve excellence in their business and [email protected] ISO 9001:2008 professional practices. Contact John at www.geokon.com registered [email protected]

50 Geo-Strata l geoinstitute.org 082009_Geostrata_ATA Micropile2.qxd:082009_Geostrata_ATA Micropile2 12/2/09 1:12 PM Page 1

Micropiles allow two basement levels to be added below the existing American Trucking Association. Washington, DC

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Soil Mixing www.schnabel.com Atlanta 770-971-6455 Boston 508-303-3642 Tiebacks Chicago 847-639-8900 Denver 303-696-7268 Houston 281-531-1103 Underpinning Orlando 407-566-0199 Philadelphia 610-277-2950 San Francisco 925-947-1881 Washington, D.C. 301-657-3060 EOE • DFWP CORE BITS ence the Terzaghi lecture and doze Fifth International Conference Get Instant ns of technical presentations cover on Scour and Erosion (ICSE) ing all areas of the profession. Toas November 7-10, 2010 Updates t the G-I 2010 Hero, J. Michael Duncan, Holiday Inn Gateway From the at the Hero and Awards Luncheon. Mee t ASCE authors Clyde Baker, Vau San Francisco, CA. G-I. ghan Griffiths and Gordon Fenton a www.icse-5.org t the ASCE Bookstore. Browse the Ex hibit Hall. Take the special Techni This G-I conference will highlight the Twitter at http://twitter.com/ cal Tour, plus much more. The Geo-Ins multi-disciplinary nature of scour GeoInstitute titute Board Need and erosion problems and solutions s which require approaches that merge Facebook at www.facebook.com/pages/ expertise in a wide variety of fields. Geo-Institute-of-ASCE/129517101742 You Here is your opportunity Planned discussion topics include to b emerging theoretical developments, G-I Individual and Organizational field and laboratory studies, field Member names appear in bold ecome involved in the leadership of applications of technology, and case throughout CoreBits. the Geo-Institute. The G-I’s Nomi histories. The conference will feature nations and Elections Committee is so keynote speakers in plenary sessions liciting nominations for one seat on t followed by concurrent sessions. he Board of Governors beginning ICSE-5 will also offer short courses G-I News in October 2010. As immediate G- before the conference and technical I Past President, Jean-Louis Briaud tours following the conference. Addi- stated, “By being on the Board, I met tional events include a welcome and Your 2010 Voluntary many more G-I members than I would networking reception with posters in Contribution Helps Students have had a chance to otherwis the Exhibition Hall. e. It gave me an opportunity to hel The students need your help. p the profession continue to improv Your 2010 Geo-Institute Voluntary e. Plus, it taught me more about how t Professional Development Cor- Contribution goes entirely to the o reach consensus on tough issues, ab ner Student Participation Fund, which out how to find win-win solutions helps defray the costs for students to during discussions, how to keep the March 2, 2010: Noon-1:30 p.m. ET: compete at the Geo-Challenge at the big picture in mind at all times, An Overview of Geosynthetics and annual Congress. Please contribute and how to put the members first.” P Their Major Applications when you renew your membership, ast President Steve Wright or donate online by logging in at s March 10 & 17: Noon-1:30 PM ET: www.asce.org. Choose “Select Institutes tates: “I rekindled old friendships and (LRFD) for Geotechnical Engineering, and Make Contributions.” made many new friends and professi Two-Part Series onal contacts that I most likely w ould never had made otherwise. If For information: https://secure.asce.org/ GeoFlorida 2010 you like working with really nice peop ASCEWebsite/Webinar/ListWebinar.aspx February 20-24, 2010 le, there is no better job. If there i Palm Beach County s one word to describe my experienc Convention Center e, it was FUN!” Each nominee must be a Symposium on Benchmarking West Palm Beach, Florida membe Surface Wave Method r www.geocongress.org Geo-Risk Conference in good standing of the G-I f or at least one year prior to the e Summer 2011 Daily Registration Rates are lection and be willing to serve on th Call for Participation Deadline: Available. e Board for at least three year March 31, 2010 s. The submission deadline is Friday Uncover new developments in , March 26, 2010. For information: h Practitioners and researchers are geotechnical engineering analysis, ttp://content.geoinstitute.org/file modeling, and design. Be a part of invited to this symposium organized modeling, and design. Be a part of s/pdf/NominationsProcess.pdf Fifth by the G-I’s Geophysical Engineering

52 Geo-Strata l geoinstitute.org Committee. This symposium will Viggiani who will present the lecture document the state of different “Sand deformation at the grain scale protocols, such as Multichannel quantified through x-ray imaging”; Analysis of Surface Waves (MASW), Dr. Tim Senden who will present Spectral Analysis of Surface “Micro-petrophysical experiments via Waves (SASW), and Refraction tomography and simulation”; and Microtremor (ReMi), for analyzing Dr. Anders Kaestner’s “Geological the surface wave data. The Organizing samples analyzed with neutron Committee requests submissions imaging methods” as the kickoff for to the benchmarking exercise by the session which includes novel analyzing a surface wave data set technologies. collected at a well-characterized site. Participants can also provide written papers for inclusion in a symposium Members in that will be organized as part of the symposium. For information: http:// the News saswbench.ce.ufl.edu. Questions? Dr. Dennis Hiltunen at [email protected]fl.edu. Ronald J. Ebelhar Joins ASTM International Board of G-I Twitter Brings You Quick Directors News Updates Ronald J. Twitter is a social networking tool Ebelhar, for posting very brief updates, or a senior “tweets.” The G-I launched its Twitter principal feed in April 2009 to announce with H.C. updates to its website and other Nutting, a relevant news items. Since then, Terracon over 240 updates have been posted company in and more than 230 persons have Cincinnati, become registered G-I followers. OH, was Visit our Twitter feed at http://twitter. Ronald Ebelhar named to com/GeoInstitute. You can check for a three- updates or “follow” us using a Twitter year term on the ASTM International account, an RSS reader, or one of the board of directors. Ebelhar joined many other web applications that McClelland Engineers in Houston, TX work with Twitter. Spread the word. as a staff engineer/consultant in 1977 for a 10-year span. He then served as division manager and vice president GeoX 2010 for Rust Environment & Infrastructure (and its predecessors, S&ME, www.cee.lsu.edu/geox2010/ Westinghouse and SEC Donohue) workshop/default.htm in Cincinnati, OH, before taking the position of vice president with H.C. GeoX2010, the 3rd International Nutting in 1996. He assumed his Workshop on X-Ray CT for current role in 2007. Geomaterials, March 1-3, 2010,

New Orleans, LA is co-sponsored As a project manager for geotechnical by the Geo-Institute. The conference and environmental engineering will serve as an exchange forum projects worldwide, Ebelhar has to discuss the latest advances and provided design and consulting developments in the applications services for commercial, industrial, of x-ray computed tomography. transportation, waste disposal, and Keynote lecturers include: Dr. Cino public utility projects; geotechnical

Geo-Strata l geoinstitute.org 53 CORE BITS engineering design and construction, including site soil engineering firms in a variety response under seismic, cyclic and dynamic loadings; and of capacities including project marine geosciences and engineering field explorations. management and deep foundation and anchored earth Ebelhar, who joined ASTM International in 1980, serves retention design. His credits as chair of Committee D18 on Soil and Rock. An ASTM include participating in several fellow and 2003 Award of Merit recipient, he received geo-engineering and construction the R.S. Ladd Standards Development Award in 2008 research projects. He is the for D7400, Test Methods for Downhole Seismic Testing; current secretary of the Geo- the Woodland G. Shockley Award in 2007; the A .Ivan Institute’s Deep Foundations Johnson Outstanding Achievement Award in 2002; Special Committee, and the Soil Service Awards in 1993 and 1986; and the Committee D18 Improvement Committee. Tony Tony Marinucci Technical Editor’s Award for STP 1213, Dynamic Geotechnical has also been an active volunteer Testing II, in 1995. and committee member for many ADSC, ASCE, and DFI initiatives. Marinucci Joins ADSC Staff McCook Becomes ASDSO Honorary Member Antonio Marinucci, P.E., recently joined the ADSC headquarters staff as Director of Member Services as he Danny K. McCook, P.E., was selected as an Honorary completes his Ph.D. studies in geotechnical engineering Member of The Association of State Dam Safety Officials at the University of Texas at Austin. Tony brings several (ASDSO) by its Board of Directors in 2009. McCook is years of experience working for geo-construction specialty an independent consultant specializing in geotechnical contractors, a major general contractor, and geotechnical review and design of earthen embankments and levees. He

54 Geo-Strata l geoinstitute.org Micropiles • Caissons • Driven / Drilled Piles • Augercast Piles Ground Anchors / Tiebacks • Excavation and Drainage Rock / Soil Nailing • Grouting • Sheet Piling Bridges and Complex Structures • Concrete Foundations Lock and Dam Construction • Steel Erection Demolition / Brownfields Redevelopment

1000 John Roebling Way Saxonburg, PA 16056 Office: 724-443-1533 Fax: 724-443-8733 www.braymanconstruction.com 

  KEHOE TESTING & ENGINEERING, INC. (KTE) operates two specially designed, 4 axle CPT rigs that weigh over 31 tons. Other CPT vendors advertise that they operate “30 ton” trucks; but in (l to r) ASDSO President David Gutierrez and McCook reality, most other CPT rigs are 3 axle trucks that retired in October 2008 after working for over 40 years weigh 20-25 tons. Our CPT rigs are based out of as a civil engineer and geotechnical specialist with the Southern California, but we travel throughout the western & Midwestern US. National Design, Construction, and Soil Mechanics Center of the USDA Natural Resources Conservation Service In addition to the heavier CPT rigs, we use an in Fort Worth, TX. He has extensive experience in filter extendable rod guide, hydraulic clamping system design, modeling for stability, seepage, and consolidation and higher capacity 15 sq. cm cones that help give analyses. McCook has participated in numerous forensic us the ability to push deeper and through denser evaluations and has designed over 500 small earthen soils. We also have automatic seismic hammers embankments in the National Resources Conservation built into the front jack pad, printing and data transmittal capabilities directly from the field, several Service (NRCS) programs. He also has presented papers at smaller “anchor down” limited access CPT rigs and 16 ASDSO meetings and presented webinars on reviews many other capabilities including soil, vapor and for embankment projects. McCook authored numerous groundwater sampling. Please check out our publications used by the NRCS for criteria and guidance website at www.kehoetesting.com or call our office in the design of earthen embankments. He is a registered for additional information. professional engineer in Texas and a member of ASCE, the

United States Society on Dams (USSD), and the Association We designed KTE’s rigs knowing the tremendous advantage of having CPT rigs with 20-25% higher of State Dam Safety Officials (ASDSO). pushing capacity. We are often called out to sites where other CPT vendors have hit shallower “refusal.” Why not use a larger CPT rig for your next CPT project? Because when using CPT, BIGGER is BETTER!!!

Edward Graf  In Memoriam: Edward Graf  5415 Industrial Drive The grouting industry has lost a “Grouting Great.” Edward Huntington Beach, CA 92649-1518 Office (714) 901-7270 / Fax (714) 901-7289 Dutton Graf, former Geo-Institute member and pioneer www.kehoetesting.com

in grouting and foundation engineering, passed away of lung disease on December 16, 2009 at Kaiser Hospital

56 Geo-Strata l geoinstitute.org FIND OUT MORE TOLL FREE 877-846-3165 WWW.GEOSTRUCTURES.COM

Engineered Earth Structures & Foundations DESIGN, BUILD, DONE

Ask about our Green Advantage certified staff! CORE BITS in Honolulu, HI. He was just two weeks shy of his 85th for the Utah County I-15 Corridor Expansion (I-15 birthday. A native Californian, Graf was a World War II CORE) project. The project is Utah’s first attempt at a Navy veteran, engineer, contractor, inventor, consultant, “fixed-price/best-design” project. Kleinfelder is part of the and pilot. His technical and professional achievements Provo River Contractors (PRC) team and their contract included: ASCE – Life Member and past chair of Committee is for $10.8 million to $13.6 million of the $1.7 billion 552 – Geotechnical Cement Grouting; ASCE Grouting project. Kleinfelder will perform geotechnical services with Committee past chair; Martin S. Kapp Foundation challenges such as ground settlement, embankment slope Engineering Award, 1990; Fellow ACI (American Concrete stability, liquefaction, lateral spreading and seismic activity. Institute); Who’s Who in Engineering since 1982; six patents; and nine published papers. Read his “We are so proud to be a part of the team that was obituary at: http://content.geoinstitute.org/files/pdf/EGraf.pdf selected for this important project in one of our country’s fastest-growing counties,”said Houman Makarechi, P.E., Kleinfelder senior vice president and transportation division manager. “Our team’s dedication, expertise, and experience G-I Organizational in the transportation sector all played an important role in our success.” Member News Moretrench GRL and PDI Retain Authorized Provider Status Moretrench American The International Association for Continuing Education Corporation and Training (IACET) renewed GRL Engineers and Pile chairman John Dynamics’ prestigious Authorized Provider status through Donohoe died on 2010. Providers are the only organizations approved to December 2, 2009. offer IACET Continuing Education Units (CEUs). The He had served as Florida Board of Professional Engineers also renewed GRL chairman since 1995. Engineers’ status as an Authorized Provider of Professional Donohoe joined Development Hours in Florida through 2011. Moretrench in 1964, immediately after “GRL and PDI are proud of our education programs which graduating from train more than 120 engineers each year in foundation the University of testing and analysis skills so that they stay on the cutting Notre Dame with edge,” stated Gina Beim, P.E., who manages the continuing a degree in civil education and training programs for the companies. engineering. Over John Donohoe the course of a long To retain this status, the companies completed a rigorous and distinguished career application process, including a review by an IACET site with the company, he visitor, and successfully demonstrated adherence to the advanced to hold the positions of president from 1982 to ANSI/IACET 1-2007 Standard addressing the design, 2002 and chief executive officer from 1995 to 2007. development, administration, and evaluation of its programs. A similar process was necessary to retain the Throughout his career, he was active in the civil engineering status of provider in Florida. community. He served as President of the Construction Institute of ASCE, President of AGC of New Jersey, GRL has been providing deep foundation testing and National Director of AGC of America, President of The analysis services for more than 35 years. Sister company Moles, and President and Trustee of CIAP of New Jersey. PDI manufactures state-of-the-art systems for deep He was selected as Man of the Year of AGC of New foundation testing and installation monitoring. Jersey in 2001 and in 2004 received The Moles Award for Outstanding Achievement in Construction, a tribute to his lifetime accomplishments. He was a 2009 recipient Kleinfelder Selected for UDOT I-15 of the prestigious ASCE Opal Award for “innovation and Reconstruction Project excellence in construction of civil engineering projects and/or programs.” Most recently, he was elected president Kleinfelder was selected to perform geotechnical services of GCA of New York. Read his obituary at http://content.

58 Geo-Strata l geoinstitute.org geoinstitute.org/files/pdf/JFDObituaryProfessionalOrgs.doc An engineering scholarship fund was established in John’s G-I Chapter News name. Mail donations to the John F. Donohoe Scholarship Fund c/o Moretrench American Corporation, 100 Stickle Expand Your GT Group’s Exposure. Become a G-I Avenue, Rockaway, NJ 07866. Contact Moretrench American Chapter. at 973.627.2100 for details. Alternatively, donations can be made to St. John’s Soup Kitchen, 22 Mulberry Street, Increase your membership recruitment efforts by converting Newark, NJ 07122. your ASCE Section/Branch Geotechnical Group to a G-I Chapter or by forming a G-I Chapter. It is strongly encouraged by ASCE, and no fees or dues are required. The Nicholson Awarded Treatment Contract at simple process to become a G-I Chapter is posted on the Hanford Site G-I Web site at http://content.geoinstitute.org/groups/index.html. Benefits of affiliating with the G-I are also posted, as is a CH2M HILL Plateau Remediation Company (CH2M HILL) PowerPoint presentation. recently awarded Carpenter Drilling and Nicholson a construction subcontract worth $330K for a jet injection test program at the U.S. Department of Energy’s 100N Area on the Hanford Site in Richland, WA. The test program is Allied Organizations expected to take approximately three weeks to complete.

Using jet grouting methods, Nicholson will construct three 2011 Pan-Am CGS Geotechnical Conference permeable reactive barrier test sections by injecting ground October 2-6, 2011 fishbone slurry, known as apatite, as well as a phosphate Toronto, Ontario, Canada solution. Permeable reactive barriers in the 100N Area are www.panam-cgc2011.ca/ being designed to protect the nearby Columbia River by sequestering and immobilizing strontium-90 in the soil and groundwater so it can safely decay in place. The Canadian Geotechnical Society and the International Fishbone and phosphate solutions will be injected using Society for Soil Mechanics and Geotechnical Engineering, Nicholson’s proprietary JETPLUS jet grouting system. invite you to the 14th Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE), the 64th Canadian Geotechnical Conference (CGC) and the Terra ‘s Book Value per Share Sets Another 5th Pan-American Conference on Teaching and Learning of Record Geotechnical Engineering (PCTLGE) at the Sheraton Centre Hotel in Toronto, Ontario, Canada. Terra Insurance Company’s book value per share set another new all-time high at the end of the third quarter, reaching $260.06 at September 30, 2009. This represents a 6ICEG - 2010 7.1% increase since January 1, 2009. Terra’s earnings since Sixth International Congress on Environmental January 1 were $10.39 per share, almost 20% ahead of what they were on September 30, 2008. Geotechnics November 8-12, 2010 “Terra has generated net income in every calendar quarter of New Delhi, India its existence as a risk retention group,” said Terra President www.6iceg.org and CEO David L. Coduto. “This is not the first economic downturn we’ve weathered profitably, and I’m confident it The Indian Geotechnical Society (IGS) will host this won’t be the last.” conference on behalf of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). The Terra provides a variety of professional liability insurance Organizing Committee is guided by a Conference Advisory products to civil, environmental, and geoprofessional Committee, as well as the TC5 (Technical Committee on engineering firms that gross from $300,000 to more than Environmental Geotechnics) of ISSMGE, and a National $100 million annually. Advisory Committee of IGS. The theme of the Congress is Environmental Geotechnics for Sustainable Development. More than 400 delegates, including 250 from abroad, will

Geo-Strata l geoinstitute.org 59 CORE BITS gather to discuss latest developments. Previous Congress Thomas Selected U.S. Professor of the Year locations include: Edmonton, Canada (1994), Osaka, Japan (1996), Lisbon, Portugal (1998 ), Rio de Janeiro, Brazil (2002), and Cardiff, UK (2006).

“Design, Analysis, and Failures of Geosyntheti- cally Reinforced Retaining Walls and Steep Soil Slopes” Short Course

This March 31, 2010 short course will be held at the Geosynthetic Institute, 475 Kedron Avenue, Folsom, PA. The course will present the origin, growth, and costs of mechanically stabilized earth walls and soil slopes using geosynthetic ( and geogrids) reinforcement. Design and analysis will be focused on and illustrated using two computer codes; MSEW and ReSSA, generated for the Federal Highway Administration by Professor Leshchinsky. Wall and slope failures will be presented along with the major cause of such failures, lack of drainage considerations. Proper drainage designs will then be Rob Thomas (r) with student, Stetson Wilson. Photo courtesy of the University of Montana Western. explained. Throughout the course, the various geosynthetics tests necessary for design will be demonstrated. Eight PDH’s are available. For information: http://content.geoinstitute.org/ University of Montana Western environmental sciences files/pdf/GSIOneDayShortCourseDesignAnalysisFailures.doc professor Rob Thomas was named Outstanding Baccalaureate Colleges Professor of the Year by The Carnegie Foundation for the Advancement of Teaching and the Council for Advancement and Support of Education Industry News (CASE).

New Discoveries Could Improve Climate Thomas has been a faculty member at Montana Western Projections for 16 years. During that time, he helped transform the institution into the first and only public university in New discoveries about the deep ocean’s temperature the U.S. to offer block scheduling. Under this scheduling variability and circulation system could help improve system, students take one class at a time, three hours per projections of future climate conditions. The deep ocean day for eighteen days earning the same credits over a year is affected more by surface warming than previously as students do in traditional multiple-course scheduling thought, and this understanding allows for more accurate models. predictions of factors such as sea level rise and ice volume changes. High ocean surface temperatures have also been Thomas left a tenure track position in the Ivy League at found to result in a more vigorous deep ocean circulation Vassar College because he recognized Montana Western’s system. This increase results in a faster transport of large potential. He states that his and Montana’s Western’s recent quantities of warm water, with possible impacts including successes are particularly gratifying. For more information: reduction of sea ice extent and overall warming of the http://news.umwestern.edu/2009/11/rob-thomas-selected-u-s- Arctic. “The deep ocean is relatively unexplored, and we professor-of-the-year/ need a true understanding of its many complex processes”, said U.S. Geological Survey Director Marcia McNutt. An understanding of climate change and its impacts based Fifth International Conference on Recent on sound, objective data is a keystone to the type of long- Advances in Geotechnical Earthquake Engineer- term strategies and solutions that are being discussed now ing and Soil Dynamics at the United Nations conference in Copenhagen. For http://5geoeqconf2010.mst.edu information: www.clim-past.net/5/769/2009/cp-5-769-2009.html Registration is open for this May 24-29, 2010, San Diego,

60 Geo-Strata l geoinstitute.org GEO_EDTseries_ad.qxd:UTF_EDT7_05_ad.qxd 1/11/10 12:06 PM Page 1

CA conference and symposium in honor of professor I.M. Idriss. Register now to select the best spot for your booth and obtain the reduced early Unsurpassed Flexibility & Dependability registration fee. Professionals from The ExcaDrill® Series of drilling attachments from Watson provide unique more than 40 countries will present drilling capabilities for a wide range of applications. Long reach, low overhead, up, their recent research findings. The down, over and under obstacles on varying slopes are now easily accessible exchange of information during the conference will advance the state of with an ExcaDrill. Check out these models and our full line of rigs the art and practice in several areas at watsonusa.com. and will give definitive direction to future work. Earthquake, civil, ExcaDrill® Series structural, and geotechnical engineers, geologists, scientists, teachers, builders, contractors, and other professionals worldwide are invited to attend and join in the discussion at this conference.

2009 NOVA Award Winners

The 2009 NOVA award, instituted in 1989 to recognize innovations EDT-10 EDT-7 that have proven to be significant advances that have had positive, important effects on construction to EDT-5 improve quality and reduce cost, was recently presented to Michael Adams, Robert Barrett, and Warren Schlatter, P.E., P.S. This year, the Construction Innovation Forum selected the innovative project “Geosynthetically Reinforced Soil (GRS) Bridge Abutments in Defiance County, Ohio” from among 35 nominations. Made in America...Best in the World. watsonusa.com Adams works with the FHWA at the Turner Fairbanks Highway Research Fort Worth, Texas Center; Barrett serves on the Board of 817-927-8486 Directors of Soil Nail Launcher, Inc.; and Schlatter is the County Engineer for Defiance County, OH.

CONTECH Announces January Price Increase

CONTECH Construction Products Inc. announced a January 12, 2010 PVC pipe products. “Increased order price increase,” said Steve Spanagel, price increase for its corrugated metal activity in the steel industry along president of CONTECH Sales. and PVC products. The price increase with increased raw material and will be 8.9% for all corrugated steelmaking input costs from our metal products and 9.0% for all suppliers are the main reasons for this

Geo-Strata l geoinstitute.org 61 CORE BITS

Geo-Institute International Conference on Scour and Erosion November 7-10, 2010 Upcoming Holiday Inn Gateway Conferences San Francisco, California www.icse-5.org

Visit www.geoinstitute.org/events.html for links to these and Geo-Frontiers 2011 other upcoming events: March 13-16, 2011 Sheraton Dallas GeoFlorida 2010 Dallas, TX February 20-24, 2010 www.geofrontiers11.com/ Palm Beach County Convention Center West Palm Beach Marriott Hilton Palm Beach Airport To submit information for Geo-Strata magazine, or West Palm Beach, FL possible posting on the Geo-Institute website at www. www.geocongress.org geoinstitute.org, send us brief news about your recent honors, awards, special appointments, promotions, etc. Earth Retention 2010 High-resolution photos must be sent as separate pdf, tif, August 1-August 4, 2010 or jpeg files. Send to [email protected]. Sales-oriented Hyatt Regency Bellevue content should be directed to Dianne Vance, Director of Bellevue, WA Advertising at [email protected]. www.er2010.org

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INHelp the victims of the Haiti earthquakeHAITI with the most important text message you’ll . ever send. Text “Haiti” to 90999 and a $10 donation will be added to your phone bill.* Your contribution helps the Red Cross provide food, water and shelter. Haiti is calling for help: Answer with a text.

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62 Geo-Strata l geoinstitute.org 2010

Earth Retention 2010

August 1 - August 4, 2010 Hyatt Regency Bellevue Bellevue, Washington

www.er2010.org

join us for these 2010 Geo-Institute conferences International

Conference on November 7-10, 2010 Holiday Inn Golden Gateway Scour and Erosion San Francisco, California

www.icse-5.org

ICSE-5 Advances in Geotechnical Engineering

MARK YOUR CALENDAR FOR THE GEOTECHNICAL EVENT OF 2011

Where engineering design and construction comes together with dynamic products and applications

e objective of the Event is to share new developments in geotechnical engineering technologies. Attendees will be exposed to the latest state-of-the-art-and-practice as applied to geotechnical engineering.

Abstracts due 8 March 2010 www.geofrontiers11.com

Geo-Frontiers 2011 is co-organized by Under the auspices of Includes GRI-24 Annual Conference

GeoFront11SaveDateAd_FP.indd 1 2/4/10 7:53:05 AM Advances in Geotechnical Engineering

MARK YOUR CALENDAR FOR THE GEOTECHNICAL EVENT OF 2011

Where engineering design and construction comes together with dynamic products and applications

e objective of the Event is to share new developments in geotechnical engineering technologies. Attendees will be exposed to the latest state-of-the-art-and-practice as applied to geotechnical engineering.

Abstracts due 8 March 2010 www.geofrontiers11.com

Geo-Frontiers 2011 is co-organized by Under the auspices of Includes GRI-24 Annual Conference

GeoFront11SaveDateAd_FP.indd 1 2/4/10 7:53:05 AM