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Gis-Based Approaches to Slope Stability Analysis and Earthquake -Induced Landslide Hazard Zonation

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Gis-Based Approaches to Slope Stability Analysis and Earthquake -Induced Landslide Hazard Zonation Gis-Based Approaches To Slope Stability Analysis And Earthquake -Induced Landslide Hazard Zonation Item Type Thesis Authors Luo, Huayang Download date 03/10/2021 23:28:52 Link to Item http://hdl.handle.net/11122/8896 GIS-BASED APPROACHES TO SLOPE STABILITY ANALYSIS AND EARTHQUAKE-INDUCED LANDSLIDE HAZARD ZONATION A THESIS Presented to the Faculty of the University of Alaska Fairbanks in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHIFOSOPHY By Huayang Luo, B.S., M.S. Fairbanks, Alaska May 2006 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 3229739 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. ® UMI UMI Microform 3229739 Copyright 2006 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. GIS-BASED APPROACHES TO SLOPE STABILITY ANALYSIS AND EARTHQUAKE-INDUCED LANDSLIDE HAZARD ZONATION By Huayang Luo RECOMMENDED: Advisory Committee Chair —Chair, Department) of Mining and Geological — Engineering APPROVED: Dean/Co liege of Engineering and Mines Dean of the Graduate School Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Abstract This dissertation presents newly developed GIS-based deterministic and probabilistic approaches for slope stability analysis and earthquake-induced landslide hazard zonation. The described approaches combine numerical slope stability analysis with GIS spatial analysis to evaluate earthquake-induced slope failures, both shallow and deep-seated. The study has four major research components. The first component is a GIS-based procedure which was developed based on one-, two-, and three-dimensional (ID, 2D, and 3D) deterministic approaches to slope stability analysis and landslide hazard zonation. Slope stability methods in the GIS-based procedure included the infinite slope model, the block sliding model, the ordinary method of slices, the Bishop simplified method, and the Hovland’s column method. The second component focuses on causative factors analysis of earthquake- induced landslide hazards. This component also discusses the determination of peak ground acceleration for slope stability analysis. The third component consists of an evaluation of the topographic effect of ground motion and the seismic response in the Balsamo Ridge area in Nueva San Salvador. The fourth component is concerned with the regional and site-specific landslide hazard zonation, using newly developed models for landslide hazard assessment in Nueva San Salvador. The slope stability and landslide susceptibility were mapped in terms of slope stability index (factor of safety, critical acceleration, Newmark displacement, failure probability, and reliability index). The landslides triggered by an earthquake on January 13, 2001 in El Salvador provide a setting for the calibration of results from GIS-based approaches. The procedures developed in this research proved to be feasible and cost-effective for slope stability analysis and earthquake-induced landslide hazard zonation. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. iv Table of Contents Page Signature Page............................................................................................................................ i Title P a g e..................................................................................................................................... ii A bstract...................................................................................................................................... iii Table of Contents......................................................................................................................iv List of Figures ........................................................................................................................... ix List of Tables ........................................................................................................................... xv Acknowledgments ................................................................................................................. xvii Chapter 1 Introduction............................................................................................................ 1 1.1 Introduction ......................................................................................................... 1 1.2 GIS Applications in Landslide Hazard Zonation .......................................... 4 1.3 Objective and Scope ........................................................................... 5 Chapter 2 Earthquake-Induced Landslides and Analysis Methods............................10 2.1 Characteristics of Earthquake-Induced Landslides ........................................10 2.2 Seismic Slope Stability Analysis ....................................................................... 14 2.2.1 General Methods ...................................................................................... 14 2.2.2 Pseudo-Static Analysis .............................................................................. 15 2.2.3 Newmark Displacement M ethod ............................................................21 2.3 Review of GIS-based Approaches to Landslide Hazard Zonation .............. 25 2.3.1 Landslide Susceptibility and Hazard Mapping .....................................25 2.3.2 General Methodology ...............................................................................27 2.3.3 Direct Mapping ..........................................................................................30 2.3.4 Heuristic Approaches (Geomorphic Analyses) ....................................31 2.3.5 Statistical Methods .................................................................................... 31 2.3.6 Deterministic Methods ..............................................................................35 2.3.7 Probabilistic M ethods ...............................................................................38 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Chapter 3 Study Area: Nueva San Salvador, El Salvador .............................................41 3.1 Introduction ..........................................................................................................41 3.2 Study Area: Nueva San Salvador ...................................................................... 43 3.3 G eology .................................................................................................................45 3.3.1 Geological Setting of El Salvador ........................................................... 45 3.3.2 Geology of Nueva San Salvador and Vicinity ...................................... 47 3.4 Historic Destructive Earthquakes .....................................................................49 3.5 Landslides in Nueva San Salvador Area .......................................................... 49 Chapter 4 Causative Factor Analysis and GIS Data Processing .................................. 57 4.1 Introduction .......................................................................................................... 57 4.2 Geology .................................................................................................................57 4.2.1 Lithology ..................................................................................................... 57 4.2.2 Geotechnical Parameters ...........................................................................61 4.2.3 Groundwater .............................................................................................. 61 4.3 Geomorphology ...................................................................................................63 4.3.1 Slope Angle and H eight ............................................................................63 4.3.2 Slope Aspect .............................................................................................. 65 4.3.3 Depth and Dimension of Slope Failure..................................................65 4.4 Earthquakes .......................................................................................................... 67 4.5 Vegetation .............................................................................................................68 4.5.1 Root Strength ............................................................................................. 68 4.5.2 Vegetation Index ........................................................................................68 4.6 GIS Data Preparation and Processing ...............................................................70 Chapter 5 Ground Motion and Topographic
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