Liquefaction of Soils During Earthquakes
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SECTION 3 Erosion Control Measures
SECTION 3 Erosion Control Measures 1. SEEDING When • Bare soil is exposed to erosive forces from wind and or water. Why • A cost effective way to prevent erosion by protecting the soil from raindrop impact, flowing water and wind. • Vegetation binds soil particles together with a dense root system, increasing infiltration thereby reducing runoff volume and velocity. Where • On all disturbed areas except where non-vegetative stabilization measures are being used or where seeding would interfere with agricultural activity. Scheduling • During the recommended temporary and permanent seeding dates outlined below. • Dormant seeding is acceptable. How 1. Site Assessment. Determine site physical characteristics including available sunlight, slope, adjacent topography, local climate, proximity to sensitive areas or natural plant communities, and soil characteristics such as natural drainage class, texture, fertility and pH. 2. Seed Selection. Use seed with acceptable purity and germination tests that are viable for the planned seeding date. Seed that has become wet, moldy or otherwise damaged is unacceptable. Select seed depending on, location and intended purpose. A mixture of native species for permanent cover may provide some advantages because they have coevolved with native wildlife and other plants and typically play an important function in the ecosystem. They are also adapted to the local climate and soil if properly selected for site conditions; can dramatically reduce fertilizer, lime and maintenance requirements; and provide a deeper root structure. When re- vegetating natural areas, introduced species may spread into adjacent natural areas, native species should be used. Noxious or aquatic nuisance species shall not be used (see list below). If seeding is a temporary soil erosion control measure select annual, non-aggressive species such as annual rye, wheat, or oats. -
Seismic Pore Water Pressure Generation Models: Numerical Evaluation and Comparison
th The 14 World Conference on Earthquake Engineering October 12-17, 2008, Beijing, China SEISMIC PORE WATER PRESSURE GENERATION MODELS: NUMERICAL EVALUATION AND COMPARISON S. Nabili 1 Y. Jafarian 2 and M.H. Baziar 3 ¹M.Sc, College of Civil Engineering, Iran University of Science and Technology, Tehran, Iran ² Ph.D. Candidates, College of Civil Engineering, Iran University of Science and Technology, Tehran, Iran ³ Professor, College of Civil Engineering, Iran University of Science and Technology, Tehran, Iran ABSTRACT: Researchers have attempted to model excess pore water pressure via numerical modeling, in order to estimate the potential of liquefaction. The attempt of this work is numerical evaluation of excess pore water pressure models using a fully coupled effective stress and uncoupled total stress analysis. For this aim, several cyclic and monotonic element tests and a level ground centrifuge test of VELACS project [1] were utilized. Equivalent linear and non linear numerical models were used to evaluate the excess pore water pressure. Comparing the excess pore pressure buildup time histories of the numerical and experimental models showed that the equivalent linear method can predict better the excess pore water pressure than the non linear approach, but it can not concern the presence of pore pressure in the calculation of the shear strain. KEYWORDS: Excess pore water pressure, effective stress, total stress, equivalent linear, non linear 1. INTRODUCTION Estimation of liquefaction is one of the main objectives in geotechnical engineering. For this purpose, several numerical and experimental methods have been proposed. An important stage to predict the liquefaction is the prediction of excess pore water pressure at a given point. -
Guideline for Extraction of Ground Motion Parameters for Scientific Hydraulic Fracturing Review Panel
Guideline for Extraction of Ground Motion Parameters for Scientific Hydraulic Fracturing Review Panel Alireza Babaie Mahani Ph.D. P.Geo. Mahan Geophysical Consulting Inc. Victoria, BC Email: [email protected] Website: www.mahangeo.com Executive Summary The Scientific Review of Hydraulic Fracturing in British Columbia (2019) provides the key findings of a scientific panel on the topic of hydraulic fracturing in British Columbia and the associated environmental risks. As indicated in the report, the panel recommends preparation of guidelines for standard calculation of earthquake magnitude and ground motion parameters. Since Babaie Mahani and Kao (2019 and 2020) have addressed the methodology for calculation of local magnitude in two publications, this report deals with standard methodologies for extraction of ground motion parameters from recorded earthquake waveforms. The guidelines include data from both types of seismic sensors that are used for induced seismicity monitoring; seismometers that record ground motion velocities and accelerometers that are designed to record strong ground accelerations at short distances. Waveforms from the November 30, 2018 induced earthquake with moment magnitude (Mw) of 4.6 that occurred in northeast British Columbia within the Montney unconventional resource play are presented for better understanding of the processing steps. Data Formats The standard format that is used to archive earthquake data is called the SEED format (Standard for the Exchange of Earthquake Data; https://ds.iris.edu/ds/nodes/dmc/data/formats/seed/). When both the time series data and metadata are archived in one file, the name full-SEED is also used. miniSEED is the stripped down version of SEED that only includes waveform data (https://ds.iris.edu/ds/nodes/dmc/data/formats/miniseed/). -
2021 Oregon Seismic Hazard Database: Purpose and Methods
State of Oregon Oregon Department of Geology and Mineral Industries Brad Avy, State Geologist DIGITAL DATA SERIES 2021 OREGON SEISMIC HAZARD DATABASE: PURPOSE AND METHODS By Ian P. Madin1, Jon J. Francyzk1, John M. Bauer2, and Carlie J.M. Azzopardi1 2021 1Oregon Department of Geology and Mineral Industries, 800 NE Oregon Street, Suite 965, Portland, OR 97232 2Principal, Bauer GIS Solutions, Portland, OR 97229 2021 Oregon Seismic Hazard Database: Purpose and Methods DISCLAIMER This product is for informational purposes and may not have been prepared for or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary data and information sources to ascertain the usability of the information. This publication cannot substitute for site-specific investigations by qualified practitioners. Site-specific data may give results that differ from the results shown in the publication. WHAT’S IN THIS PUBLICATION? The Oregon Seismic Hazard Database, release 1 (OSHD-1.0), is the first comprehensive collection of seismic hazard data for Oregon. This publication consists of a geodatabase containing coseismic geohazard maps and quantitative ground shaking and ground deformation maps; a report describing the methods used to prepare the geodatabase, and map plates showing 1) the highest level of shaking (peak ground velocity) expected to occur with a 2% chance in the next 50 years, equivalent to the most severe shaking likely to occur once in 2,475 years; 2) median shaking levels expected from a suite of 30 magnitude 9 Cascadia subduction zone earthquake simulations; and 3) the probability of experiencing shaking of Modified Mercalli Intensity VII, which is the nominal threshold for structural damage to buildings. -
Recommended Guidelines for Liquefaction Evaluations Using Ground Motions from Probabilistic Seismic Hazard Analyses
RECOMMENDED GUIDELINES FOR LIQUEFACTION EVALUATIONS USING GROUND MOTIONS FROM PROBABILISTIC SEISMIC HAZARD ANALYSES Report to the Oregon Department of Transportation June, 2005 Prepared by Stephen Dickenson Associate Professor Geotechnical Engineering Group Department of Civil, Construction and Environmental Engineering Oregon State University ODOT Liquefaction Hazard Assessment using Ground Motions from PSHA Page 2 ABSTRACT The assessment of liquefaction hazards for bridge sites requires thorough geotechnical site characterization and credible estimates of the ground motions anticipated for the exposure interval of interest. The ODOT Bridge Design and Drafting Manual specifies that the ground motions used for evaluation of liquefaction hazards must be obtained from probabilistic seismic hazard analyses (PSHA). This ground motion data is routinely obtained from the U.S. Geologocal Survey Seismic Hazard Mapping program, through its interactive web site and associated publications. The use of ground motion parameters derived from a PSHA for evaluations of liquefaction susceptibility and ground failure potential requires that the ground motion values that are indicated for the site are correlated to a specific earthquake magnitude. The individual seismic sources that contribute to the cumulative seismic hazard must therefore be accounted for individually. The process of hazard de-aggregation has been applied in PSHA to highlight the relative contributions of the various regional seismic sources to the ground motion parameter of interest. The use of de-aggregation procedures in PSHA is beneficial for liquefaction investigations because the contribution of each magnitude-distance pair on the overall seismic hazard can be readily determined. The difficulty in applying de-aggregated seismic hazard results for liquefaction studies is that the practitioner is confronted with numerous magnitude-distance pairs, each of which may yield different liquefaction hazard results. -
CPT-Geoenviron-Guide-2Nd-Edition
Engineering Units Multiples Micro (P) = 10-6 Milli (m) = 10-3 Kilo (k) = 10+3 Mega (M) = 10+6 Imperial Units SI Units Length feet (ft) meter (m) Area square feet (ft2) square meter (m2) Force pounds (p) Newton (N) Pressure/Stress pounds/foot2 (psf) Pascal (Pa) = (N/m2) Multiple Units Length inches (in) millimeter (mm) Area square feet (ft2) square millimeter (mm2) Force ton (t) kilonewton (kN) Pressure/Stress pounds/inch2 (psi) kilonewton/meter2 kPa) tons/foot2 (tsf) meganewton/meter2 (MPa) Conversion Factors Force: 1 ton = 9.8 kN 1 kg = 9.8 N Pressure/Stress 1kg/cm2 = 100 kPa = 100 kN/m2 = 1 bar 1 tsf = 96 kPa (~100 kPa = 0.1 MPa) 1 t/m2 ~ 10 kPa 14.5 psi = 100 kPa 2.31 foot of water = 1 psi 1 meter of water = 10 kPa Derived Values from CPT Friction ratio: Rf = (fs/qt) x 100% Corrected cone resistance: qt = qc + u2(1-a) Net cone resistance: qn = qt – Vvo Excess pore pressure: 'u = u2 – u0 Pore pressure ratio: Bq = 'u / qn Normalized excess pore pressure: U = (ut – u0) / (ui – u0) where: ut is the pore pressure at time t in a dissipation test, and ui is the initial pore pressure at the start of the dissipation test Guide to Cone Penetration Testing for Geo-Environmental Engineering By P. K. Robertson and K.L. Cabal (Robertson) Gregg Drilling & Testing, Inc. 2nd Edition December 2008 Gregg Drilling & Testing, Inc. Corporate Headquarters 2726 Walnut Avenue Signal Hill, California 90755 Telephone: (562) 427-6899 Fax: (562) 427-3314 E-mail: [email protected] Website: www.greggdrilling.com The publisher and the author make no warranties or representations of any kind concerning the accuracy or suitability of the information contained in this guide for any purpose and cannot accept any legal responsibility for any errors or omissions that may have been made. -
Bray 2011 Pseudostatic Slope Stability Procedure Paper
Paper No. Theme Lecture 1 PSEUDOSTATIC SLOPE STABILITY PROCEDURE Jonathan D. BRAY 1 and Thaleia TRAVASAROU2 ABSTRACT Pseudostatic slope stability procedures can be employed in a straightforward manner, and thus, their use in engineering practice is appealing. The magnitude of the seismic coefficient that is applied to the potential sliding mass to represent the destabilizing effect of the earthquake shaking is a critical component of the procedure. It is often selected based on precedence, regulatory design guidance, and engineering judgment. However, the selection of the design value of the seismic coefficient employed in pseudostatic slope stability analysis should be based on the seismic hazard and the amount of seismic displacement that constitutes satisfactory performance for the project. The seismic coefficient should have a rational basis that depends on the seismic hazard and the allowable amount of calculated seismically induced permanent displacement. The recommended pseudostatic slope stability procedure requires that the engineer develops the project-specific allowable level of seismic displacement. The site- dependent seismic demand is characterized by the 5% damped elastic design spectral acceleration at the degraded period of the potential sliding mass as well as other key parameters. The level of uncertainty in the estimates of the seismic demand and displacement can be handled through the use of different percentile estimates of these values. Thus, the engineer can properly incorporate the amount of seismic displacement judged to be allowable and the seismic hazard at the site in the selection of the seismic coefficient. Keywords: Dam; Earthquake; Permanent Displacements; Reliability; Seismic Slope Stability INTRODUCTION Pseudostatic slope stability procedures are often used in engineering practice to evaluate the seismic performance of earth structures and natural slopes. -
Living on Shaky Ground: How to Survive Earthquakes and Tsunamis
HOW TO SURVIVE EARTHQUAKES AND TSUNAMIS IN OREGON DAMAGE IN doWNTOWN KLAMATH FALLS FRom A MAGNITUde 6.0 EARTHQUAke IN 1993 TSUNAMI DAMAGE IN SEASIde FRom THE 1964GR EAT ALASKAN EARTHQUAke 1 Oregon Emergency Management Copyright 2009, Humboldt Earthquake Education Center at Humboldt State University. Adapted and reproduced with permission by Oregon Emergency You Can Prepare for the Management with help from the Oregon Department of Geology and Mineral Industries. Reproduction by permission only. Next Quake or Tsunami Disclaimer This document is intended to promote earthquake and tsunami readiness. It is based on the best SOME PEOplE THINK it is not worth preparing for an earthquake or a tsunami currently available scientific, engineering, and sociological because whether you survive or not is up to chance. NOT SO! Most Oregon research. Following its suggestions, however, does not guarantee the safety of an individual or of a structure. buildings will survive even a large earthquake, and so will you, especially if you follow the simple guidelines in this handbook and start preparing today. Prepared by the Humboldt Earthquake Education Center and the Redwood Coast Tsunami Work Group (RCTWG), If you know how to recognize the warning signs of a tsunami and understand in cooperation with the California Earthquake Authority what to do, you will survive that too—but you need to know what to do ahead (CEA), California Emergency Management Agency (Cal EMA), Federal Emergency Management Agency (FEMA), of time! California Geological Survey (CGS), Department of This handbook will help you prepare for earthquakes and tsunamis in Oregon. Interior United States Geological Survey (USGS), the National Oceanographic and Atmospheric Administration It explains how you can prepare for, survive, and recover from them. -
Title of Paper
Raw earth construction: is there a role for unsaturated soil mechanics ? D. Gallipoli, A.W. Bruno & C. Perlot Université de Pau et des Pays de l'Adour, Laboratoire SIAME, Anglet, France N. Salmon Nobatek, Anglet, France ABSTRACT: “Raw earth” (“terre crue” in French) is an ancient building material consisting of a mixture of moist clay and sand which is compacted to a more or less high density depending on the chosen building tech- nique. A raw earth structure could in fact be described as a “soil fill in the shape of a building”. Despite the very nature of this material, which makes it particularly suitable to a geotechnical analysis, raw earth construc- tion has so far been the almost exclusive domain of structural engineers and still remains a niche market in current building practice. A multitude of manufacturing techniques have already been developed over the cen- turies but, recently, this construction method has attracted fresh interest due to its eco-friendly characteristics and the potential savings of embodied, operational and end-of-life energy that it can offer during the life cycle of a structure. This paper starts by introducing the advantages of raw earth over other conventional building materials followed by a description of modern earthen construction techniques. The largest part of the manu- script is devoted to the presentation of recent studies about the hydro-mechanical properties of earthen materi- als and their dependency on suction, water content, particle size distribution and relative humidity. A raw earth structure therefore consists of com- pacted moist soil and may be described in geotech- 1 DEFINITION OF EARTHEN nical terms as a “soil fill in the shape of a building”. -
Chapter 3. the Crust and Upper Mantle
Theory of the Earth Don L. Anderson Chapter 3. The Crust and Upper Mantle Boston: Blackwell Scientific Publications, c1989 Copyright transferred to the author September 2, 1998. You are granted permission for individual, educational, research and noncommercial reproduction, distribution, display and performance of this work in any format. Recommended citation: Anderson, Don L. Theory of the Earth. Boston: Blackwell Scientific Publications, 1989. http://resolver.caltech.edu/CaltechBOOK:1989.001 A scanned image of the entire book may be found at the following persistent URL: http://resolver.caltech.edu/CaltechBook:1989.001 Abstract: T he structure of the Earth's interior is fairly well known from seismology, and knowledge of the fine structure is improving continuously. Seismology not only provides the structure, it also provides information about the composition, crystal structure or mineralogy and physical state. In subsequent chapters I will discuss how to combine seismic with other kinds of data to constrain these properties. A recent seismological model of the Earth is shown in Figure 3-1. Earth is conventionally divided into crust, mantle and core, but each of these has subdivisions that are almost as fundamental (Table 3-1). The lower mantle is the largest subdivision, and therefore it dominates any attempt to perform major- element mass balance calculations. The crust is the smallest solid subdivision, but it has an importance far in excess of its relative size because we live on it and extract our resources from it, and, as we shall see, it contains a large fraction of the terrestrial inventory of many elements. In this and the next chapter I discuss each of the major subdivisions, starting with the crust and ending with the inner core. -
A Review of the Seismic Hazard Zonation in National Building Codes in the Context of Eurocode 8
A REVIEW OF THE SEISMIC HAZARD ZONATION IN NATIONAL BUILDING CODES IN THE CONTEXT OF EUROCODE 8 Support to the implementation, harmonization and further development of the Eurocodes G. Solomos, A. Pinto, S. Dimova EUR 23563 EN - 2008 A REVIEW OF THE SEISMIC HAZARD ZONATION IN NATIONAL BUILDING CODES IN THE CONTEXT OF EUROCODE 8 Support to the implementation, harmonization and further development of the Eurocodes G. Solomos, A. Pinto, S. Dimova EUR 23563 EN - 2008 The mission of the JRC is to provide customer-driven scientific and technical support for the conception, development, implementation and monitoring of EU policies. As a service of the European Commission, the JRC functions as a reference centre of science and technology for the Union. Close to the policy-making process, it serves the common interest of the Member States, while being independent of special interests, whether private or national. European Commission Joint Research Centre Contact information Address: JRC, ELSA Unit, TP 480, I-21020, Ispra(VA), Italy E-mail: [email protected] Tel.: +39-0332-789989 Fax: +39-0332-789049 http://www.jrc.ec.europa.eu Legal Notice Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use which might be made of this publication. A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server http://europa.eu/ JRC 48352 EUR 23563 EN ISSN 1018-5593 Luxembourg: Office for Official Publications of the European Communities © European Communities, 2008 Reproduction is authorised provided the source is acknowledged Printed in Italy Executive Summary The Eurocodes are envisaged to form the basis for structural design in the European Union and they should enable engineering services to be used across borders for the design of construction works. -
Italy and China Sharing Best Practices on the Sustainable Development of Small Underground Settlements
heritage Article Italy and China Sharing Best Practices on the Sustainable Development of Small Underground Settlements Laura Genovese 1,†, Roberta Varriale 2,†, Loredana Luvidi 3,*,† and Fabio Fratini 4,† 1 CNR—Institute for the Conservation and the Valorization of Cultural Heritage, 20125 Milan, Italy; [email protected] 2 CNR—Institute of Studies on Mediterranean Societies, 80134 Naples, Italy; [email protected] 3 CNR—Institute for the Conservation and the Valorization of Cultural Heritage, 00015 Monterotondo St., Italy 4 CNR—Institute for the Conservation and the Valorization of Cultural Heritage, 50019 Sesto Fiorentino, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-06-90672887 † These authors contributed equally to this work. Received: 28 December 2018; Accepted: 5 March 2019; Published: 8 March 2019 Abstract: Both Southern Italy and Central China feature historic rural settlements characterized by underground constructions with residential and service functions. Many of these areas are currently tackling economic, social and environmental problems, resulting in unemployment, disengagement, depopulation, marginalization or loss of cultural and biological diversity. Both in Europe and in China, policies for rural development address three core areas of intervention: agricultural competitiveness, environmental protection and the promotion of rural amenities through strengthening and diversifying the economic base of rural communities. The challenge is to create innovative pathways for regeneration based on raising awareness to inspire local rural communities to develop alternative actions to reduce poverty while preserving the unique aspects of their local environment and culture. In this view, cultural heritage can be a catalyst for the sustainable growth of the rural community.