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Evaluation of Soil Dilatancy The Influence of Grain Shape on Dilatancy Item Type text; Electronic Dissertation Authors Cox, Melissa Reiko Brooke Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 24/09/2021 03:25:54 Link to Item http://hdl.handle.net/10150/195563 THE INFLUENCE OF GRAIN SHAPE ON DILATANCY by MELISSA REIKO BROOKE COX ________________________ A Dissertation Submitted to the Faculty of the DEPARTMENT OF CIVIL ENGINEERING AND ENGINEERING MECHANICS In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY WITH A MAJOR IN CIVIL ENGINEERING In the Graduate College THE UNIVERISTY OF ARIZONA 2 0 0 8 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Melissa Reiko Brooke Cox entitled The Influence of Grain Shape on Dilatancy and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy ___________________________________________________________________________ Date: October 17, 2008 Muniram Budhu ___________________________________________________________________________ Date: October 17, 2008 Achintya Haldar ___________________________________________________________________________ Date: October 17, 2008 Chandrakant S. Desai ___________________________________________________________________________ Date: October 17, 2008 John M. Kemeny Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. ___________________________________________________________________________ Date: October 17, 2008 Dissertation Director: Muniram Budhu 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: ________________________________ Melissa Reiko Brooke Cox 4 ACKNOWLEDGEMENTS There are many people whom I would like to acknowledge for guiding me down the path to my doctoral degree. As troublesome and tiring as it was at times, my advisor, Dr. Budhu, was a constant force in motivating me and encouraging me through this journey. His commitment to me and my research continues to be far exceeding my expectations of an advisor/graduate student relationship. Dr. Budhu not only supported my research ideas and opinions, he also continually challenged me to extend my thinking beyond my comfort zone. He has become a huge inspiration and counsel to me, in school as well as in other aspects of my life. I am also very grateful to my doctoral committee members including Dr. Haldar, Dr. Desai and Dr. Kemeny. They have each unselfishly given their time, patience and expertise in order for me to successfully complete my research. I appreciate all of the continued support I have received throughout my education from all of my professors. I would like to thank the staff of the Department of Civil Engineering, namely, Karen Van Winkle, Mick Mathieu, Therese Lane, Steve Albanese, Tom Demma. I am especially grateful to Karen for being my “mommy” away from home. She was there for me every step of the way, no matter how good or bad things were. Karen will always have a special place in my heart. I extend many thanks to my colleagues, especially Sandeep Mahajan, Juan Lopez and Dustin Agnew. Having them around has made the long hours of studying more enjoyable and bearable, to say the least. I am grateful to my friends that have been there for me during this chapter of my life, especially Alie Joyner, Raina Gomez-Moger, Hannah Mendes, and Marissa Bonilla. I thank Shannon Boothe from the bottom of my heart for being my best friend and never giving up on me. I also thank Conor Jackson for pushing me to succeed and never allowing myself to settle. Finally, I would like to thank my family for giving me the opportunity to follow my dreams, especially my parents. Both of them have been there for me through good and bad, and I could never thank them enough for all of the sacrifices they have made for me so that I may achieve every one of my goals. I appreciate everything they have ever done to make me the woman I am today. 5 I dedicate this dissertation to my parents for their unconditional love and support. 6 TABLE OF CONTENTS LIST OF ILLUSTRATIONS........................................................................................10 LIST OF TABLES .........................................................................................................13 ABSTRACT....................................................................................................................14 CHAPTER 1: INTRODUCTION................................................................................16 1.1 Introduction..........................................................................................................16 1.2 Statement of the Problem.....................................................................................17 1.3 Objectives and Scope of Research.......................................................................19 1.3.1 Main Goal................................................................................................19 1.3.2 Hypothesis................................................................................................19 1.3.3 Objectives and Tasks ...............................................................................19 1.4 Expected Novel Contributions.............................................................................21 1.5 Organization of Dissertation................................................................................22 1.6 Conventions and Units.........................................................................................24 1.7 Notations and Symbols ........................................................................................24 CHAPTER 2: LITERATURE REVIEW....................................................................27 2.1 Introduction..........................................................................................................27 2.2 Shear Strength......................................................................................................27 2.2.1 Peak Friction Angles................................................................................31 2.2.2 Stress-Dilatancy Relationships................................................................37 2.3 Grain Shape Quantification..................................................................................41 2.4 Digital Image Capturing Device ..........................................................................48 2.5 Image Processing Tool.........................................................................................51 7 TABLE OF CONTENTS – Continued 2.6 Recent Similar Research......................................................................................52 2.6 Recent Similar Research......................................................................................52 2.7 Summary of Findings...........................................................................................53 CHAPTER 3: DILATANCY EVALUATION USING EXISTING DATA.............54 3.1 Introduction..........................................................................................................54 3.2 Experimental Observations..................................................................................54 3.3 Discussion of Dilatancy Evaluation.....................................................................60 3.3.1 Influence of Sand Type on Dilatancy ......................................................60 3.3.2 Influence of Grain Properties on Dilatancy .............................................61 3.4 Summary of Findings...........................................................................................63 CHAPTER 4: GRAIN SHAPE ANALYSIS...............................................................64 4.1 Introduction..........................................................................................................64 4.2 Experiment...........................................................................................................64 4.2.1 Materials and Preparation ........................................................................64 4.2.2 Methods of Capturing Digital Images......................................................67 4.2.3 Image Processing for Shape Quantification.............................................69
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