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Physical Modeling of Landslide Generated PHYSICAL MODELING OF LANDSLIDE GENERATED TSUNAMIS IN VARIOUS SCENARIOS FROM FJORDS TO CONICAL ISLANDS A Dissertation Presented to The Academic Faculty by Brian C. McFall In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the School of Civil and Environmental Engineering Georgia Institute of Technology August 2014 COPYRIGHT © 2014 BY BRIAN C. MCFALL PHYSICAL MODELING OF LANDSLIDE GENERATED TSUNAMIS IN VARIOUS SCENARIOS FROM FJORDS TO CONICAL ISLANDS Approved by: Dr. Hermann M. Fritz, Advisor Dr. Donald R. Webster School of Civil and Environmental School of Civil and Environmental Engineering Engineering Georgia Institute of Technology Georgia Institute of Technology Dr. Kevin A. Haas Dr. Paul A. Work School of Civil and Environmental Estuarine Hydrodynamics and Engineering Sediment Transport Georgia Institute of Technology U.S. Geological Survey Dr. Josef D. Dufek School of Earth and Atmospheric Sciences Georgia Institute of Technology Date Approved: June 23, 2014 ACKNOWLEDGEMENTS It has truly been an honor to pursue a doctoral degree at the Georgia Institute of Technology, but I could not have accomplished this degree without the guidance and encouragement of several people. I would like to thank my family, whose never ending love and encouragement has made this academic endeavor possible. I would like to express my deepest gratitude to my advisor, Dr. Hermann Fritz, for his support and guidance throughout this project. I am also grateful to Dr. Paul Work, Dr. Kevin Haas, Dr. Donald Webster and Dr. Josef Dufek for serving on my committee. Their comments and suggestions greatly improved this dissertation. Last but not least, I would like to thank my fellow graduate students especially, Xiufeng Yang, Brittany Bruder, Stephanie Smallegan, Chatchawin Srisuwan and David Young for their help and support throughout my tenure at Georgia Tech. This work was supported by National Science Foundation, Division of Civil, Mechanical and Manufacturing Innovation through grant numbers CMMI-0936603, CMMI-0927178, CMMI-0421090 and CMMI-0402490. Additionally, this work was supported by the Department of Defense through the Science, Mathematics & Research for Transformation (SMART) fellowship. The scientific and technical support Network for Earthquake Engineering and Simulation (NEES) and the O.H. Hindsdale wave research facility is acknowledged. iii TABLE OF CONTENTS Page ACKNOWLEDGEMENTS ............................................................................................. iii LIST OF TABLES ........................................................................................................... ix LIST OF FIGURES ........................................................................................................... x SUMMARY ................................................................................................................. xxiv I INTRODUCTION ....................................................................................................... 1 II LITERATURE REVIEW ............................................................................................ 4 2.1 Introduction ......................................................................................................... 4 2.2 Landslides ........................................................................................................... 5 2.2.1 Landslide Dynamics ................................................................................ 5 2.2.2 Granular Landslide Experiments ............................................................ 8 2.3 Modeling of Landslide Generated Tsunamis .................................................... 10 2.3.1 2D Block Slide Models ......................................................................... 10 2.3.2 3D Block Slide Models ......................................................................... 17 2.3.2 Piston Slide Models .............................................................................. 20 2.3.3 Granular Slide Models .......................................................................... 22 2.3.4 Numerical Modeling of Landslide Generated Tsunamis ....................... 31 iv 2.4 Runup and Rundown ......................................................................................... 34 2.5 Edge Waves ..................................................................................................... 38 2.6 Conclusions from Previous Studies .................................................................. 42 2.7 Identified Research Gaps .................................................................................. 43 III EXPERIMENTAL SETUP ........................................................................................ 45 3.1 Introduction ....................................................................................................... 45 3.2 Dimensional Analysis ....................................................................................... 45 3.3 Physical Model .................................................................................................. 49 3.4 Pneumatic Landslide Tsunami Generator ......................................................... 54 3.5 Granular Landslide Material ............................................................................. 57 3.6 Instrumentation Deployed in the Tsunami Wave Basin ................................... 58 3.6.1 Wave Gauges ........................................................................................ 58 3.6.2 Camera Setup ........................................................................................ 60 3.6.3 Particle Image Velocimetry Camera Setup ........................................... 63 3.6.4 Multi-transducer Acoustic Array .......................................................... 66 3.6.5 Data Acquisition System ...................................................................... 68 3.7 Uncertainty in Measurements .......................................................................... 68 3.7.1 Error Analysis ....................................................................................... 68 v 3.7.2 Uncertainty in Landslide Measurements ............................................. 70 3.7.3 Experiment Repeatability ..................................................................... 72 3.8 Experiment Methodology ................................................................................. 73 3.8.1 Experimental Procedure ....................................................................... 73 3.8.2 Range of Nondimensional Parameters .................................................. 75 IV GRANULAR LANDSLIDE ..................................................................................... 78 4.1 Introduction ...................................................................................................... 78 4.2 Landslide Shape ............................................................................................... 80 4.3 Landslide Width ............................................................................................... 88 4.4 Landslide Motion ............................................................................................. 93 4.5 Landslide Deposit ............................................................................................ 95 V WAVE PROPAGATION ........................................................................................ 102 5.1 Introduction .................................................................................................... 102 5.2 Wave Amplitude Attenuation ........................................................................ 106 5.2.1 Wave Amplitude Attenuation – Planar Hill Slope ............................. 108 5.2.2 Comparison with Previous Studies ..................................................... 111 5.2.3 Wave Amplitude Attenuation – Conical Hill Slope ........................... 113 5.2.4 Lateral Hill Slope Effects ................................................................... 115 vi 5.2.5 Landslide Granulometry Effects ........................................................ 117 5.3 Wave Period ................................................................................................... 119 5.4 Wave Celerity ................................................................................................. 125 5.5 Wave Length .................................................................................................. 129 5.6 Wave Nonlinearity ......................................................................................... 134 5.7 Energy Conversion ......................................................................................... 139 VI WAVE RUNUP AND RUNDOWN ....................................................................... 146 6.1 Introduction .................................................................................................... 146 6.2 Lateral Wave Runup ....................................................................................... 147 6.2.1 Lateral Wave Runup Introduction ..................................................... 147 6.2.2 Maximum Runup and Rundown ........................................................ 150 6.2.3 Maximum Runup at Slide Impact Prediction ..................................... 155 6.2.4 Maximum Runup Adjacent to Slide Impact Prediction ..................... 159 6.2.5 Location of Maximum Runup Adjacent to Impact Prediction
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