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Landslide Risk Management and Ohio Database A LANDSLIDE RISK MANAGEMENT AND OHIO DATABASE A Dissertation Presented to The Graduate Faculty of The University of Akron In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Gridsana Pensomboon May, 2007 LANDSLIDE RISK MANAGEMENT AND OHIO DATABASE Gridsana Pensomboon Dissertation Approved: Accepted: Advisor Department Chair Dr. Robert Liang Dr. Wieslaw Binienda Committee Member Dean of the College Dr. Wieslaw Binienda Dr. George Haritos Committee Member Dean of Graduate School Dr. Craig Menzemer Dr. George Newkome Committee Member Date Dr. Yueh-Jaw Lin Committee Member Dr. Chien-Chung Chan ii ABSTRACT Landslides or slope/embankment failures along highways present potential safety and operational hazards. Road closures or detours due to the landslides impact the regional economy when services and commercial goods cannot be distributed to their destinations and the extra fuel and maintenance costs for additional mileages due to road detours. With the limited resources to the Ohio Department of Transportation (ODOT), it becomes imperative that a decision-making tool is developed to effectively manage the landslide hazards impacting highways in Ohio. The objective of this research study is to develop a landslide risk management system. An innovative web-enabled database, built upon GIS platform is developed for real-time managing of landslide spatial and temporal data. A landslide hazard rating system has been developed to provide a means to numerically score and rate the relative hazard or risk level of each site. The associated statistical and cluster analysis results of 37 Ohio landslide sites collected as a pilot database validates the effectiveness of the rating system. An alternative method to assist decision-making is also developed for managing the risks of potential highway slope failures. Usually, decision to manage risk on the failed highway project depends on many parameters. Some of them are based expert opinion and difficult to quantify and standardize. Relying only on expert experience may result in bias and irrational decision. In this dissertation, a method to deal with expert opinion was proposed. The linguistic fuzzy technique is used to transform the expert iii judgment into numerical values. The application of multi-criteria decision function standardizes the qualitative and quantitative parameters; therefore, the parameters (criteria) having different units can be combined. The importance of each risk parameter is determined using the factor analysis technique. It essentially involves the use of the best linear combination of the parameters to account for variance in data. The information of 37 landslide sites in Ohio is also used to illustrate the application of the developed method. It is shown that the multi-criteria decision making approach, in conjunction with factor analysis techniques can promote rationale decision-making for managing the risk of potentials roadway slope failures. iv DEDICATION Dedicated to my parents v ACKNOWLEDGEMENT This dissertation cannot be accomplished without help and encouragement by these people. First of all, I would like to express my appreciation to my advisor, Professor Robert Liang, for his guidance, vision, inspiration, motivation and generous support. I have learned a lot from him, not only in engineering disciplines but also a person of a great merit. What I have learned from him is a life-time experience that I can use for the rest of my life. Thanks to all committee members including Professor Wieslaw Binienda, Professor Craig Menzemer, Professor Chien-Chung Chan and Professor Yueh-Jaw Lin for valuable discussions, comments and reviews of this dissertation. Thanks to Mr. Kirk Beach, and Mr. Gene Guiger in ODOT, for research support, information and valuable discussion. Special thanks to Ms. Kimberly Stone, Ms. Christina Christian, Secretary, Mr. David McVaney, Lab Technician, all staffs and colleagues for cooperative and kindly environment. Thanks to Mr. Kevin Butler, for cooperative and valuable discussion in GIS. Thanks to Dr. Frank Feng for his contribution in the development of the landslide GIS-internet database. Finally, I would like to thank my parents, Boonchob and Uthai, and my brothers, Apichat and Saritpong, for continuous support, love and encouragement throughout the course of study. vi TABLE OF CONTENTS Page LIST OF TABLES…………………………………………………………………. xi LIST OF FIGURES………………………………………………………………... xiii CHAPTER I. INTRODUCTION………………………………………………………….. 1 1.1 Statement of the problem………………………………..................... 1 1.2 Objectives of the study………………………………….................... 3 1.3 Organization of the dissertation……………………………………... 4 II. BACKGROUNDS AND LITERATURE REVIEWS……………………... 6 2.1 Overview……………………………………………………….......... 6 2.2 Landslide Mitigation Needs……………………………..................... 6 2.3 Factor Simulating Landslides……………………………………….. 8 2.3.1 Stability of Slopes…………………………………............... 8 2.3.2 Landslide Causal Factors…………………………………… 10 2.4 Classification and Types of Landslides……………………………... 12 2.4.1 Fall………………………………………………………....... 15 2.4.2 Topple……………………………………………………….. 15 2.4.3 Slide……………………………………………………......... 15 2.4.4 Spread………………………………………………….......... 17 2.4.5 Flow……………………………………………………......... 17 vii 2.5 Landslide Prone Locations……………………………....................... 18 2.5.1 Under Cutting Rock Slope Where Bedding Planes Dip Toward the Roadway…………….......................................... 19 2.5.2 Natural Occurring Spring…………………............................ 19 2.5.3 Side-Hill Cut-and-Fill Sections……………………………... 19 2.5.4 Poorly Drained Location……………………………………. 19 2.5.5 Vertical or Nearly Vertical Rock Faces Near Roadway……. 20 2.5.6 Very High Fill………………………………………............. 20 2.6 Signs of Slope Movement…………………………………………… 22 2.6.1 Tension Cracks on Roadway or on Slope above the Roadway…………………………………………………….. 22 2.6.2 Escarpments in or above the Roadway ….............................. 22 2.6.3 Sunken Guardrail……………………………………………. 22 2.6.4 Dips in Grade …………………………………………......... 23 2.6.5 Debris on Roadway………………………………................. 23 2.6.6 Bulge above, on, or below Roadway………………………... 23 2.6.7 Poor Drainage (Surface Water)……………………............... 24 2.6.8 Poor Drainage (Subsurface Water)…………………………. 25 2.6.9 Erosion…………………………………………………........ 25 2.6.10 Changes in Features…….…………………………………... 26 2.6.11 Changes in Structures……...……………………................... 26 2.7 Concepts of Landslide Risk Management…………………………... 28 2.8 Application of Database and GIS towards Landslide Risk Management………………………………………………………… 29 viii 2.9 Reviews of Existing Landslide Rating Systems….............................. 32 2.9.1 Landslide Management in Hong Kong …….......................... 33 2.9.1.1 Ranking Systems For Cut and Fill Slopes………….. 33 2.9.1.2 Classification of Squatter Area……………………... 34 2.9.1.3 Classification of Undeveloped Land………………... 35 2.9.2 Oregon Department of Transportation…................................ 35 2.9.2.1 Preliminary Rating………………………………….. 35 2.9.2.2 Detail Rating………………………………………... 36 2.9.3 New York State Department of Transportation…………….. 37 2.9.4 Washington State Department of Transportation…………… 39 2.9.5 Tennessee Department of Transportation......................................................................... 41 III. LANDSLIDE FIELD RECONNAISANCE FORM AND DATA COLLECTION PROCESS…………………………………………………. 43 3.1 Overview………………………………………………………......... 43 3.2 Landslide Reconnaissance Form and Landslide Reconnaissance Process……………………………………………………………… 44 3.2.1 Landslide Observation Report……………………………… 44 3.2.2 Landslide Hazard Form Part A and B………………………. 44 3.2.3 Landslide Hazard Form Part C………………....................... 45 IV. DEVELOPMENT OF LANDSLIDE HAZARD RATING MATRIX……... 48 4.1 Overview………………………………………………………......... 48 4.2 Locations of Thirty Seven Landslide Sites for the Study……...…… 48 4.3 Ohio DOT Landslide Hazard Rating System………......................... 52 4.4 Classification of Pilot Landslide Data by Cluster Analysis………… 56 ix 4.5 Statistical Validation………………………………………………... 66 4.6 Comparisons of Different Hazard Scoring System………………… 72 V. MULTI-CRITERIA DECISION MAKING AND FACTOR ANALYSIS APPROACH TO HIGHWAY SLOPE MANAGEMENT……………......... 74 5.1 Overview……………………………………………………….......... 74 5.2 Review of Previous Research in Decision Making ………………... 74 5.3 Risk Parameters Used in Decision-Making Model …………………. 78 5.4 Approach to the Model Development……………………………….. 80 5.5 Criteria for Describing Risk Factors..……………………………….. 86 5.6 Data Analysis………………………...……………………………… 88 5.6.1 Standardization of Data…………………………………….. 88 5.6.2 Similarity Relationships…………………………………...... 89 5.6.3 Factor Loading Determination……………………………… 92 VI. CONCLUSIONS AND RECOMMENDATIONS………………………….. 97 6.1 Summary of Important Research Results…………………………… 97 6.2 Recommendations for Implementation and Future Research ……… 100 REFERENCES:……………………...……………………………………………... 101 APPENDICES……………………………………………………………………… 106 APPENDIX A. SLOPE RATING SYSTEMS BY OTHER AGENCIES……… 107 APPENDIX B. DESIGN OF GIS-BASED WEB APPLICATION……………. 116 APPENDIX B. USER’S MANUAL……………………………………………. 130 x LIST OF TABLES Table Page 2.1 A brief list of landslide causal factors (Popescu, 1994)…………………….. 11 2.2 Abbreviated classification of slope movements (Cruden and Vernes, 1996)…………………………………………............. 14 2.3 Material types (Cruden and Varnes, 1996)…………………………............. 14 4.1 Summary of characteristics of thirty seven landslide sites…………............. 50 4.2 Summary
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