DOCSLIB.ORG

Application of Soil Nailing for Landslide Mitigation in Bhutan: a Case Study at Sorchen Bypass

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Application of Soil Nailing for Landslide Mitigation in Bhutan: a Case Study at Sorchen Bypass Application of Soil Nailing for Landslide Mitigation in Bhutan: A Case Study at Sorchen Bypass Dr. Raju Sarkar* Professor Department of Civil Engineering and Architecture, College of Science and Technology Royal University of Bhutan, Bhutan. *Corresponding Author e-mail ID: [email protected] Ritesh Kurar Undergraduate Student Department of Civil Engineering, Delhi Technological University, Delhi, India. Sangay Zangmo, Ugyen Dema, Sujan Subba, Daman Kumar Sharma Undergraduate Students Department of Civil Engineering and Architecture, College of Science and Technology, Royal University of Bhutan, Bhutan ABSTRACT Soil nail walls constructed by reinforcing the underlying soil with driving reinforcement are one of the numerous emerging slope stabilization approaches. The provided reinforcement tends to increase the shear strength of the soil as the nail affixes to stable base beneath, thus, making the slope more stable. The chief intent of this study is to establish feasibility of constructing soil nail walls at Sorchen, 17.5 km from Phuentsholing, along Phuentsholing-Thimphu highway in Bhutan; by evaluating the geological reviews and surveying the site, additionally, considering physical and chemical specifications of soil and geotechnical landslide characterization. The analysis, design and construction of permanent soil nail wall in this study has been influenced by soil nailing construction reference manuals published by Federal Highway Administration of United States Department of Transportation. This paper proposes an applicable design of soil nail wall at Sorchen bypass; verified by SNAP_2 software developed by Federal Highway Administration of United States Department of Transportation; considering the existing site soil parameters and drainage conditions. This study has been undertaken particularly at Sorchen bypass landslide, such that, the same approach/method may be utilised to arrest other similar landslide prone areas of Bhutan. KEYWORDS: Slope Stability, Soil nailing, SNAP_2, Landslide INTRODUCTION Soil nailing technique to stabilize slopes and excavations in soils has been drawn-out from New Austrian Tunnelling method (NATM), which is a system for underground excavations in rock supports. In NATM, passive metallic reinforcement, known as rock bolts, are inserted and grouted - 4963 - Vol. 22 [2017], Bund. 13 4964 into the ground, in conjunction with shotcrete facing [1-3]. Subsequently, this concept of combining passive steel reinforcement and shotcrete facing extended significantly into rock-slope and soil-slope stabilization projects [4]. Soil nails are basically rigid bars which driven into soil or pushed into boreholes which can be subsequently filled completely with grout [5]. Together with the in situ soil, they chart a coherent structural body supporting an excavation or holding the movement of an unstable slope. Soil nail walls are a widely used technology for retaining vertical cuts, nearly vertical cuts in soil and any slope which is at an angle steeper than the soil parameters would normally permit [5]. The methodology has been proven to be cost-effective and the construction faster than any other conventional support methods. On increasing account of soil–nailing technology application to reinforce soil slopes, a throng of studies on the design of nail-reinforced slopes has also been proposed. The effective designing method banks on the vigorous evaluation for stability level of reinforced slopes, which solely depend upon judicious understanding of failure behaviour and reinforcement mechanisms [6]. The interaction between soil nails, the soil behind the wall, and the facing is complex and causes redistributions of tensile forces in the nails. The mobilized shear stress along the grout-soil interface is in general not uniform and changes in direction along the nail length [7]. The tensile force that can develop in a tendon depends on the location where the nail crosses the slip surface. The location of maximum nail tensile forces is close to, but generally does not coincide with, the critical slip surface established in stability analyses. The location of the maximum load also changes from nail to nail [8] (Fig. 1). The intersection of a soil nail with the slip surface determines the length of that soil nail that can develop pull-out resistance. A multitude of methodologies have been recommended for investigating the stability of nail-reinforced slopes, such as, the finite-element method, the limit equilibrium method, and the kinematics method. By establishing varied rationales for slope failure surface and the soil– nail interaction model, numerous researchers have analysed soil nail behaviour by optimizing the design with respect to various parameters, including site conditions, geometric arrangements, length, inclination, diameter and spacing [9-14]. For practicable study, analysis and design of soil nail wall at an instable site, which has been affected by landslides for more than 20 years now [15], has been chosen (Fig. 2a, 2b, 2c). The site is near Sorchen bypass, 17.5 km away from Phuentsholing-Thimphu Highway, Bhutan. The study follows the recommendations and guidelines presented in [8] and [16]. Vol. 22 [2017], Bund. 13 4965 Figure 1: Location of maximum tensile forces in soil nails [8]. 2(a) Figure 2: Continues on the next page. Vol. 22 [2017], Bund. 13 4966 2(b) 2(c) Figure 2: Studied site of Sorchen bypass, Bhutan. (a) Site location from College of Science and Technology, Royal University of Bhutan (CST-RUB) (b) Render image of site at Sorchen bypass (c) Landslide effected zone of Sorchen bypass The manual presents the information on the design, analysis and construction of soil nail walls. It also provides LRFD (Load and Resistance Factor Design) procedures for site and lab investigation which are carried out for the suitability of construction of soil nail walls. The reference manual contains empirical formulae and range of design parameter charts to be used in the design. The Vol. 22 [2017], Bund. 13 4967 minimum factor of safety as recommended by the manual for various modes of failure of soil nail wall are mentioned in Table 1. Table 1: Minimum Factor of safety Failure modes of soil nail wall Minimum factor of safety Global stability 1.35 Sliding stability 1.3 Nail pull-out failure 2 Nail tensile failure 1.8 Facing flexure failure 1.1 Facing punching failure 1.1 METHODOLOGY AND MATERIALS The main research strategy and measures for our research processes are shown in Fig. 3. Vol. 22 [2017], Bund. 13 4968 Study on application of soil nailing at Sorchen landslide site Selection of study area Laboratory tests Chemical tests Preliminary survey Field Test Site Sieve analysis Reconnaissance Resistivity investigatio Moisture content survey Proctor test Atterberg limit test Triaxial test Result Analysis and design parameters Design and Analysis of soil nail wall Verification using SNAP -2 Soil nail wall Drawing Conclusion and documentation Figure 3: Process of adopted research methodology Vol. 22 [2017], Bund. 13 4969 FIELD SURVEY AND SUBSURFACE EXPLORATIONS 1. Total Station survey The profile of Sorchen bypass landslide site has been developed by using Total Station (Fig. 4). • Surface area of affected area or study area = 1272.431 m2 • Height of slope = 30m • Angle of slope = 600 Figure 4: Profile of Sorchen landslide site. 2. Soil Resistivity Test The Wenner 4-Point Method by far is the most used test to measure the resistivity of soil. The test provides information about the level of ground water table at certain depth and soil type of the tested area. The test has been performed in accordance to the set International standards [17]. Fig. 5 depicts the typical arrangement of Wenner 4-Point method at Sorchen bypass site. Fig. 6 depicts position of data collected from effected slope at Sorchen bypass site. Vol. 22 [2017], Bund. 13 4970 Figure 5: Typical arrangement of Wenner 4-Point method as per [18]. Figure 6: Typical arrangement of Wenner 4-Point method at Sorchen bypass site. The electrode depth (B) is kept small compared to the distance between the electrodes (A) and R is the Megger earth tester reading in ohms. The following formula gives the soil resistivity of depth A in ohm-m. ρ = 2π AR, where, A = 20B (1) Vol. 22 [2017], Bund. 13 4971 Top Middle Toe Figure 7: Position of data collected from effected slope at Sorchen bypass site. Table 2: Resistivity at various depth Type of Soil Depth(m) Resistivity(ohm-m) Top 1 1067.6 Sand mixed with various sizes of gravel 2 1632.8 Gravely silt 3 2505.72 Gravely silt Middle 1 910.6 Sand mixed with various sizes of gravel 2 653.12 3 866.64 4 678.24 5 659.4 6 640.56 7 615.44 Toe Vol. 22 [2017], Bund. 13 4972 1 558.92 2 628 3 546.36 Sand mixed with various sizes of gravel 4 628 5 590.32 6 547.8672 In Table 2, relatively higher values of resistivity test show that the ground water table is not near the ground surface and soil is basically sandy gravel. LABORATORY TESTS 1. Chemical Analysis Chemical test results of soil are found to be non-aggressive for soil nailing and as per the Soil nail manual recommendations [8, 16]. Table 3: Chemical properties of collected soil sample S. No. Properties Value Recommendations 1 Chloride content (mg/l) 1.47 < 100 2 Conc. of Sulphate (mg/l) 30.4 < 200 3 pH of sample 6.9 5-10 2. Geophysical Tests For the present study, soil sample has been amassed from Sorchen bypass, Phuentsholing- Thimphu Highway, Bhutan. The top layer of the soil has been withdrawn with the help of a shovel up to a depth of 0.5m before gathering the soil sample. The geotechnical properties of soil sample used in this study are given in Table 4. Table 4: Physical properties of soil sample Properties Value Unified soil classification system SW Maximum mass dry density (g/cc) 1.899 Optimum moisture content (%) 12.5 Internal angle of friction of soil (φ) 32.9º Cohesive strength (c) Negligible Liquid limit (%) 25.11 Plastic limit (%) 13.39 Plasticity index (%) 11.72 Vol.
Load more

Recommended publications
  • International Society for Soil Mechanics and Geotechnical Engineering
    INTERNATIONAL SOCIETY FOR SOIL MECHANICS AND GEOTECHNICAL ENGINEERING This paper was downloaded from the Online Library of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). The library is available here: https://www.issmge.org/publications/online-library This is an open-access database that archives thousands of papers published under the Auspices of the ISSMGE and maintained by the Innovation and Development Committee of ISSMGE. CASE STUDY AND FORENSIC INVESTIGATION OF LANDSLIDE AT MARDOL IN GOA Leonardo Souza,1 Aviraj Naik,1 Praveen Mhaddolkar,1 and Nisha Naik2 1PG student – ME Foundation Engineering, Goa College of Engineering, Farmagudi Goa; [email protected] 2Associate Professor – Civil Engineering Department, Goa College of Engineering, Farmagudi Goa; [email protected] Keywords: Forensic Investigations, Landslides, Slope Failure Abstract: Goa, like the rest of India is undergoing an infrastructure boom. Many infrastructure works are carried out on hill sides in Goa. As a result there is a lot of hill cutting activity going on in Goa. This has caused major landslides in many parts of Goa leading to damage and loss of property and the environment. Forensic analysis of a failure can significantly reduce chances of future slides. The primary purpose of post failure slope and stability analysis is to contribute to the safe and economic planning for disaster aversion. Western Ghats (also known as Sahyadri) is a mountain range that runs along the west coast of India. Most of Goa's soil cover is made up of laterites rich in ferric-aluminium oxides and reddish in colour. Although such laterite composition exhibit good shear strength properties, hills composing of soil possessing low shear strength are also found at some parts of the state.
    [Show full text]
  • An Experimental Study of a Nailed Soil Slope: Effects of Surcharge Loading and Nails Characteristics
    applied sciences Article An Experimental Study of a Nailed Soil Slope: Effects of Surcharge Loading and Nails Characteristics Mahmoud H. Mohamed 1 , Mohd Ahmed 1,*, Javed Mallick 1 and Pham V. Hoa 2 1 Civil Engineeg Department, College of Engineering, K. K. University, Abha 61421, Saudi Arabia; [email protected] (M.H.M.); [email protected] (J.M.) 2 Ho Chi Minh City Institute, Vietnam Academy of Science and Technology, Ho Chi Minh City 008428, Vietnam; [email protected] * Correspondence: [email protected]; Tel.: +966-172-418-439 Abstract: The earth nailing system is a ground improvement technique used to stabilize earth slopes. The behavior of the earth nailing system is dependent on soil and nailing characteristics, such as the spacing between nails, the orientation, length, and method of installation of nails, soil properties, slope height and angle, and surcharge loading, among others. In the present study, a three-dimensional physical model was built to simulate a soil nailed slope with a model scale of 1:10 with various soil nail characteristics. The simulated models consist of Perspex strips as facing and steel bars as a reinforcing system to stabilize the soil slope. Sand beds in the model were formed, using a sand raining system. The performance of nailed soil slope models under three important nails characteristics, i.e., length, spacing and orientation, with varying surcharge loading were studied. It was observed that there is a reduction in the lateral movement of slope and footing settlements with an increase in length. It was found that the slope face horizontal pressure is non-linear with different nail characteristics.
    [Show full text]
  • Management of Slope Stability in Saint Lucia
    Issue #12 December 2012 Destruction of a house caused by a rainfall-triggered landslide in an urban community - Castries, Saint Lucia. Management of Slope Stability in highlights Communities (MoSSaiC) in Saint Lucia The Challenge: affected by heavy rains and hurricanes. Even “everyday” Reducing Landslide Risk low magnitude rainfall events can trigger devastating landslides. For the city’s inhabitants, this has meant In many developing countries, landslide risk is frequent loss of property and livelihoods, and even increasing as unauthorized housing is built on already loss of lives. As with any disaster risk, this also means landslide prone hillslopes surrounding urban areas. that the island is constantly under threat of reversing This risk accumulation is driven by growing population, whatever economic progress and improvements to increasing urbanization, and poor and unplanned livelihoods it has made. Yet, by taking a community- housing settlements, which result in increased slope based approach to landslide risk management, Saint instability for the most vulnerable populations. In Lucia has shown that even extreme rainfall events, addition, the combination of steep topography of such as Hurricane Tomas in October 2010, can be volcanic islands in the Eastern Caribbean and the weathered by urban hillside communities. climate patterns of heavy rains and frequent cyclonic Saint Lucia’s success in addressing landslide haz- activity, are also natural conditions contributing to the ards in urban communities is a result of the innova- high
    [Show full text]
  • A Qljarter Century of Geotechnical Researcll
    A QlJarter Century of Geotechnical Researcll PUBLICATION NO. FHWA-RD-98-139 FEBRUARY 1999 1111111111111111111111111111111 PB99-147365 \c-c.J/t).:.. L~.i' . u.s. D~~~~~~~Co~~~~~erce~ Natronal_Tec~nical Information Service u.s. DepartillCi"li of Transportation Spnngfleld, Virginia 22161 Research, Development & Technology Turner-Fairbank Highway Research Center 6300 Georgetown Pike McLean, VA 22101-2296 FOREWORD This report summarizes Federal Highway Administration (FHW!\) geotechnical research and development activities during the past 25 years. The report incl!Jde~: significant accomplishments in the areas of bridge foundations, ground improvenl::::nt, and soil and rock behavior. A fourth category included important miscellaneous efrorts tl'12t did not fit the areas mentioned. The report vlill be useful to re~earchers and praGtitior,c:;rs in geotechnology. --------:"--; /~ /1 I~t(./l- /-~~:r\ .. T. Paul Teng (j Director, Office of Infrastructure Research, Development. and Technologv NOTiCE This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States G~)\fernm8nt assumes no liahillty for its contt?!nts or use thereof. Thir. report dor~s not constiil)tl":: a standard, specification, or regu!p,tion. The; United States Government does not endorse products or n18;1ufaGturers, Traderrlc,rks or nianufacturers' narl1es appear in thi;-, report only bec:8'I)Se they arc considered essential to tile object of the document. Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. FHWA-RD-98-139 4. Title and Subtitle 5. Report Date A Quarter Century of Geotechnical Research February 1999 6. Performing Organization Code ).
    [Show full text]
  • Stability Analysis of Slope Under Different Soil Nailing Parameters Based on the Geostudio
    International Journal of IJGE 2015 1(2): 88-92 Geohazards and Environmen t http://ijge.camdemia.ca, [email protected] Available at http://ojs.library.dal.ca/ijge Technical Notes Stability Analysis of Slope under Different Soil Nailing Parameters Based on the GeoStudio Ou-Ling Tang* and Qing-Ming Jiang Chengdu University of Technology, Chengdu 610059, P.R. China Abstract: In order to investigate the influence of different soil nailing parameters on the safety factor of a slope, the slope stability is analyzed by the GeoStudio software with different analysis methods. Soil nailing parameters (such as nail inclination, nail horizontal space, nail diameter and length) that influence the slope stability are analyzed by the Morgenstern-Price method. As the results show, the slope has the highest safety factor when the obliquity of soil nailing is about 15°, the safety factor decreases with the increase of soil-nail horizontal space with an evident acceptable space range of 2 m or less and increases linearly with the increase of soil-nail diameter and length. However when the soil- nail length equals approximately the height of the slope, the safety factor increases slowly. These results can provide a design base for field engineers. Keywords : soil nailing, retaining parameter, safety factor, Morgenstern-Price method 1 Introduction used the FLAC to simulate the change of nail’s Soil nailing is a technique of in-situ ground length, inclination, assigned the way and soil reinforcement which is widely used in the layer parameter to the influence of the horizontal foundations, pit excavations and permanent displacement of foundation pit and the greatest Sun (2007) discussed slopes.
    [Show full text]
  • Prediction of the Dynamic Soil-Pile Interaction Under Coupled Vibration Using Artificial Neural Network Approach
    Geo-Frontiers 2011 Advances in Geotechnical Engineering Geotechnical Special Publication No. 211 Dallas, Texas, USA 13-16 March 2011 Volume 1 of 6 Editors: Jie Han Daniel A. Alzamora ISBN: 978-1-61782-594-1 Printed from e-media with permission by: Curran Associates, Inc. 57 Morehouse Lane Red Hook, NY 12571 Some format issues inherent in the e-media version may also appear in this print version. Copyright© (2011) by the American Society of Civil Engineers All rights reserved. Printed by Curran Associates, Inc. (2011) For permission requests, please contact the American Society of Civil Engineers at the address below. American Society of Civil Engineers 1801 Alexander Bell Drive Reston, VA 20191 Phone: (800) 548-2723 Fax: (703) 295-6333 www.asce.org Additional copies of this publication are available from: Curran Associates, Inc. 57 Morehouse Lane Red Hook, NY 12571 USA Phone: 845-758-0400 Fax: 845-758-2634 Email: [email protected] Web: www.proceedings.com TABLE OF CONTENTS VOLUME 1 FOUNDATIONS AND GROUND IMPROVEMENT DEEP FOUNDATIONS I Prediction of the Dynamic Soil-Pile Interaction under Coupled Vibration Using Artificial Neural Network Approach .............................................................................................................................................................................................................1 Sarat Kumar Das, B. Manna, D. K. Baidya Predicting Pile Setup (Freeze): A New Approach Considering Soil Aging and Pore Pressure Dissipation...........................................11
    [Show full text]
  • Coming Full Circle 32 30 Years of Launched Soil Nails 48 Ground Stabilization for Underground Construc
    20 Ground Improvement 32 30 years of 48 Ground stabilization for 72 The Rise of UAVs – Coming Full Circle Launched Soil Nails Underground Construction in Geotechnics SEPTEMBER // OCTOBER 2016 Ground Improvement Proudly published by the Geo-Institute of ASCE SEPT/OCT GROUND 2016 IMPROVEMENT THE EVOLUTION OF LAUNCHED SOIL NAILS A 30-Year Retrospective By Colby Barrett, JD, PE, M.ASCE, and Graeme Quickfall Fiberglass launched soil nails used for bluff stabilization in Northern California. 32 GEOSTRATA SEPTEMBER/OCTOBER 2016 aunched soil nails are a unique remedial technology in the geotechnical construction Ltoolbox. These 20-ft-long, 1.5-in.-diameter nails are installed in a single shot using a compressed air “cannon” at velocities of up to 250 miles/hour, and at rates approaching 250 nails/day. The nails reinforce an unstable or potentially unstable soil mass by transferring the nail’s tensile and shear capacity into the sliding soil. However, at least as interesting as the tool itself, is the story behind the development of launched soil nail technology over the past 30 years. This story is not just one of technological innovation, advance- ment, and refinement of a specific piece of construction equipment. It stands as a testament of the innovative, bold, and resourceful char- acter of engineers and practitioners in the geotechnical construction industry. It’s also an insight into how engineers from three continents — often working independently — responded to challenges as diverse as national tragedy, shrinking infrastructure budgets, and the challenges posed by geohazards across the globe, to create a powerful new tool that continues to be refined, updated, and improved to the present day.
    [Show full text]
  • Slope Stabilization and Repair Solutions for Local Government Engineers
    Slope Stabilization and Repair Solutions for Local Government Engineers David Saftner, Principal Investigator Department of Civil Engineering University of Minnesota Duluth June 2017 Research Project Final Report 2017-17 • mndot.gov/research To request this document in an alternative format, such as braille or large print, call 651-366-4718 or 1- 800-657-3774 (Greater Minnesota) or email your request to [email protected]. Please request at least one week in advance. Technical Report Documentation Page 1. Report No. 2. 3. Recipients Accession No. MN/RC 2017-17 4. Title and Subtitle 5. Report Date Slope Stabilization and Repair Solutions for Local Government June 2017 Engineers 6. 7. Author(s) 8. Performing Organization Report No. David Saftner, Carlos Carranza-Torres, and Mitchell Nelson 9. Performing Organization Name and Address 10. Project/Task/Work Unit No. Department of Civil Engineering CTS #2016011 University of Minnesota Duluth 11. Contract (C) or Grant (G) No. 1405 University Dr. (c) 99008 (wo) 190 Duluth, MN 55812 12. Sponsoring Organization Name and Address 13. Type of Report and Period Covered Minnesota Local Road Research Board Final Report Minnesota Department of Transportation Research Services & Library 14. Sponsoring Agency Code 395 John Ireland Boulevard, MS 330 St. Paul, Minnesota 55155-1899 15. Supplementary Notes http:// mndot.gov/research/reports/2017/201717.pdf 16. Abstract (Limit: 250 words) The purpose of this project is to create a user-friendly guide focusing on locally maintained slopes requiring reoccurring maintenance in Minnesota. This study addresses the need to provide a consistent, logical approach to slope stabilization that is founded in geotechnical research and experience and applies to common slope failures.
    [Show full text]
  • Mechanically Stabilized Earth (MSE)
    Mechanically Stabilized Earth Mechanically Stabilized Earth (MSE) • Mechanically stabilized earth walls and slopes are constructed with “reinforced soil” and consist of horizontal soil reinforcing elements including such things as steel strips, steel or polymeric grids, and geotextile sheets and a facing to prevent erosion. Mechanically Stabilized Earth (MSE) • Placement of horizontal reinforcing elements of this type significantly strengthens the soil and allows construction of very steep slopes. Even vertical walls can be constructed without support from a massive structural system at the face. CONCEPT OF REINFORCED SOIL without soil reinforcement with soil reinforcement TYPES OF SOIL REINFORCEMENTS Steel strip Geostrip Various types Geogrids (extruded, bonded, woven etc) Woven geotextiles Major applications of Soil Reinforcement as per design codes – Retaining Walls & Bridge Abutments – Retaining Slopes – Soil Nailing – Embankments • On soft soil (like Sabkha in gulf countries) • Over piles • Over areas prone to subsidence TYPICAL CROSS-SECTION OF A HIGHWAY RETAINING WALL Crashbarrier FrictionSlab Pavement Drainage Pipe Facing Panel Structural Fill Backfill Soil Reinforcement Embedment Depth Transverse Drainage Pipe Levelling Pad Geotextile Foundation Soil Mechanically Stabilized Slope Abutment Center for Potential Surcharge Geosynthetic Rotational Failure Plane Reinforcement Failure xH Plane 1V Reinforced Zone 4’vertical spacing Movement and Tension Develop Along Plane of Failure Miragrid Geogrid • Laguna Beach Area, CA How Steep Can a MSE Slope Go? • > 70 deg. is a retaining wall Design of Soil Reinforced Retaining Wall Stability Checks : 1. External Stability is addressed to check against over-turning, sliding and foundation failure 2. Internal Stability is addressed to determine soil reinforcement spacing, strength & length External Stability checks PET / HS Woven Polyester •Low creep behavior for long term structural stability and more economical design.
    [Show full text]
  • Towards a Geo-Hydro-Mechanical Characterization of Landslide Classes: Preliminary Results
    applied sciences Article Towards A Geo-Hydro-Mechanical Characterization of Landslide Classes: Preliminary Results Federica Cotecchia 1 , Francesca Santaloia 2 and Vito Tagarelli 1,* 1 DICATECH, Polytechnic University of Bari, 4, 70126 Bari, Italy; [email protected] 2 IRPI, National Research Council, 4, 70126 Bari, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-3928654797 Received: 21 September 2020; Accepted: 4 November 2020; Published: 10 November 2020 Abstract: Nowadays, landslides still cause both deaths and heavy economic losses around the world, despite the development of risk mitigation measures, which are often not effective; this is mainly due to the lack of proper analyses of landslide mechanisms. As such, in order to achieve a decisive advancement for sustainable landslide risk management, our knowledge of the processes that generate landslide phenomena has to be broadened. This is possible only through a multidisciplinary analysis that covers the complexity of landslide mechanisms that is a fundamental part of the design of the mitigation measure. As such, this contribution applies the “stage-wise” methodology, which allows for geo-hydro-mechanical (GHM) interpretations of landslide processes, highlighting the importance of the synergy between geological-geomorphological analysis and hydro-mechanical modeling of the slope processes for successful interpretations of slope instability, the identification of the causes and the prediction of the evolution of the process over time. Two case studies are reported, showing how to apply GHM analyses of landslide mechanisms. After presenting the background methodology, this contribution proposes a research project aimed at the GHM characterization of landslides, soliciting the support of engineers in the selection of the most sustainable and effective mitigation strategies for different classes of landslides.
    [Show full text]
  • STUDY on SLOPE STABILIZATION by SOIL NAILING Project Report Submitted in Partial Fulfillment for the Degree of Bachelor of Technology in Civil Engineering
    STUDY ON SLOPE STABILIZATION BY SOIL NAILING Project Report submitted in partial fulfillment for the degree of Bachelor of Technology in Civil Engineering under the supervision of : Mr.Saurabh Rawat by Tushar Soni (111676) Sachin goyal (111696) to Jaypee University of Information and Technology Waknaghat, Solan – 173234, Himachal Pradesh May, 2015 Certificate This is to certify that project report entitled “ Study on slope stabilization by soil nailing and stability analysis using geo5 software”,submitted by Sachin Goyal and Tushar Soni in partial fulfillment for the award of degree of Bachelor of Technology in Civil Engineering to Jaypee University of Information Technology, Waknaghat, Solan has been carried out under my supervision.This work has not been submitted partially or fully to any other University or Institute for the award of this or any other degree or diploma. Signature of Supervisor Dr. Ashok Kumar Gupta Mr. Saurabh Rawat Head Of Department Date : External Examiner 1 Acknowledgement I thankfully acknowledge the contribution of various different journals and books, from which some of the material have been collected to enrich this project. I am very much grateful to Mr. Saurabh Rawat ,for his guidance and support throughout my project,and also for his constant inspiration from the very first day when I had started the work for this project. I would also like to give my deepest and sincerest thanks to my friends for guiding me and improving my project. Date: Sachin Goyal (111696) Tushar Soni (111676) 2 ABSTRACT Since its development in Europe in the early 1970s, soil nailing has become a widely accepted method of providing temporary and permanent earth support, underpinning and slope stabilization on many civil projects in the United States.
    [Show full text]
  • Using Thermal Integrit Integrity of Soil Nails
    USING THERMAL INTEGRITY PROFILING TO EVALUATE THE STRUCTURAL INTEGRITY OF SOIL NAILS George Piscsalko, P.E., Pile Dynamics, Inc., Solon, Ohio [email protected], Camilo Alvarez, P.E., GRL Engineers, Inc., Los Angeles, CCalifornia, Daniel S. Belardo, GRL Engineers, Inc., Solon, Ohio, Marcus Galvan, P.E., TXDOT, Austtin, Texas ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Soil nails are often utilized as a temporary or permanent earth retention technique for slope stabilization and for excavation retention for existing or new structures. Soils nails are generally advantageous as installation is relatively rapid and they can be installed beneath existing structures and where site access for equipment is limited. Due to the typically small cross-section of these elements, the inability to inspect the holes prior to grouting/concreting, and the various installation techniques utilized, quality control for assessing the integrity along the entire length is limited. Currently, quality assurance is conducted by load testing to verify the pull out capacity after installation. The load testing is typically done on a small percentage of the total number of soil nails. This paper
    [Show full text]