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Bedload Transport of Small Rivers in Malaysia

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Bedload Transport of Small Rivers in Malaysia BEDLOAD TRANSPORT OF SMALL RIVERS IN MALAYSIA by ZAHRA ZANGENEH SIRDARI Thesis submitted in fulfilment of the requirements for degree of Doctor of Philosophy May 2013 1 ACKNOWLEDGEMENTS I would like to thank all the individuals and organizations who have helped or provided the guidance during the study. Among the organisations, firstly I would like to thanks the Universiti Sains Malaysia who provided the opportunity to study in this university under fellowship scheme. I am also thankful to USM for all efforts from granting the study leave to providing all reports and drawings required for this thesis work. First and foremost I would like to express my genuine gratitude to my supervisor, Prof. Dr. Hj Aminuddin Ab. Ghani for his supervision, advice and guidance. I really was honoured to have the opportunity to work under his supervision. Also I would like to special thanks to my second Supervisor Mr. Zorkeflee Abu Hasan for his guidance and technical support. I would also like to thank River Engineering and Urban Drainage Research Centre (REDAC) and its staffs especially Mrs. Nor Mawati Mohamad, Mr. Mohd Sufian Osman, Mr. Rahim Ghazali and Mr. Khairul Nizam Abu for helping me in field measurements and data collection. I don’t have words to express my thanks to Dr. Farshid Bateni, in fact no words can express his generosity. All through this work he has provided his guidance and help in modelling and programming in MATLAB. I am also thankful to all officers, seniors, colleges and friends who helped one or another way to make possible this study. Last but not least I would extend my word of thanks to my family specially my lovely sister Nasim who helped me during all this duration of my study. ii 2 TABLE OF CONTENTS 1 ACKNOWLEDGEMENTS ................................................................................................ ii 2 TABLE OF CONTENTS ................................................................................................... iii 3 LIST OF TABLES ............................................................................................................ vii 4 LIST OF FIGURES ............................................................................................................ x 5 LIST OF ABREVIATIONS ............................................................................................. xx 6 LIST OF SYMBOLS ....................................................................................................... xxi 7 ABSTRAK ..................................................................................................................... xxiv 8 ABSTRACT .................................................................................................................. xxvi 1 CHAPTER 1- INTRODUCTION ....................................................................................... 1 1.1 Background ............................................................................................................... 1 1.2 Problem Statement .................................................................................................... 3 1.3 Objective of the Investigation ................................................................................... 5 1.4 Scope of Work .......................................................................................................... 5 1.5 Structure of Thesis .................................................................................................... 6 2 CHAPTER 2 - LITERATURE REVIEW .......................................................................... 8 2.1 Introduction .............................................................................................................. 8 2.2 Bedload Transport .................................................................................................... 8 2.3 Bedload Transport Analysis ..................................................................................... 9 2.4 Bed Load Transport Equations ............................................................................... 12 2.4.1 Performance of Bedload Transport Equations ........................................ 19 2.5 Regression Analysis ............................................................................................... 21 2.5.1 Linear Regression ................................................................................... 21 2.5.2 Multiple Linear Regression ..................................................................... 22 2.5.3 Least- Square Method ............................................................................. 23 2.5.4 Polynomial Regression ............................................................................ 24 2.5.5 Nonlinear Regression .............................................................................. 24 2.6 Soft Computing Modelling ..................................................................................... 25 iii 2.6.1 Genetic Programming (GP) ..................................................................... 26 2.6.2 Artificial Neural Network (ANN) ........................................................... 28 2.7 Application of Soft Computing Modelling in Prediction of Bedload Transport .... 30 2.8 River Channel Confluence...................................................................................... 36 2.9 Sediment Transport Modelling ............................................................................... 41 2.9.1 SSIIM ...................................................................................................... 48 2.9.1.1 SIMPLE Algorithm ................................................................. 49 2.9.1.2 Control Volume Scheme .......................................................... 49 2.9.1.3 SSIIM Application ................................................................... 50 2.10 Summary................................................................................................................. 55 3 CHAPTER 3 METHODOLOGY .................................................................................... 58 3.1 Introduction ............................................................................................................ 58 3.2 Study Area .............................................................................................................. 59 3.3 River Hydrology and Hydraulic ............................................................................. 61 3.3.1 Stream Flow Data .................................................................................... 61 3.3.2 Water Level Record ................................................................................ 61 3.3.3 Stage Discharge Data .............................................................................. 62 3.3.4 Flood Frequency Analysis ....................................................................... 63 3.4 Field Data Measurement ......................................................................................... 67 3.4.1 Flow Measurement .................................................................................. 68 3.4.2 Geometry Data ........................................................................................ 70 3.4.3 Sediment Data ......................................................................................... 72 3.4.3.1 Bed Material ............................................................................ 72 3.4.3.2 Bedload .................................................................................... 73 3.5 Techniques for Bedload Prediction ........................................................................ 75 3.5.1 Performance of Bedload Transport Equation .......................................... 76 3.5.2 Dimensional Analysis ............................................................................. 77 3.5.3 Nonlinear Regression Method (NLR) ..................................................... 78 3.5.4 Artificial Neural Network (ANN) ........................................................... 79 3.5.5 Genetic Programming Method (GP) ....................................................... 80 4 CHAPTER 4 BEDLOAD TRANSPORT CHARACTERISTICS ................................... 82 4.1 Introduction ............................................................................................................ 82 4.2 River Characteristics .............................................................................................. 83 4.2.1 Summary of River Data Collection ......................................................... 83 4.2.2 Typical Cross-Sections for the River Study Site ..................................... 87 iv 4.2.3 Parameter Affecting Bedload Transport ................................................. 90 4.3 Particle Size Distribution ........................................................................................ 93 4.4 Evaluation of Bedload Size Distribution with Increasing Shear Stress .................. 97 4.5 Fractional Transport Rate ..................................................................................... 102 4.6 Performance of Bedload Transport Equation ....................................................... 107 4.6.1 Assessment of Existing Equation for Kurau River ............................... 107 4.6.2 Prediction of Bedload Transport in Kurau River with Nonlinear Regression Method ............................................................................... 109 4.6.3 Prediction of Bedload Transport in
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