1st Edition

Dam Break Modelling, Risk Assessment and Uncertainty Analysis for Flood Mitigation IHE-PhD Thesis, Unesco-IHE, Delft, The Netherlands

By Migena Zagonjolli Copyright 2007
    142 Pages 35 Color & 23 B/W Illustrations
    by CRC Press

    142 Pages
    by CRC Press

    More than 800,000 dams and thousands of kilometers of dikes have been constructed around the world. These structures are often designed based on a statistical analysis of the discharge distribution in rivers. However, the history of construction of dams and dikes coexists with the history of failures. Hundreds of dam failure events were reported worldwide in the previous century, while every year dikes breach due to high flows in the rivers or for other reasons leading sometimes to catastrophic consequences.

    In this book a description is presented of a framework and techniques for modelling structure failure events as well as a proposal to several novel approaches for risk analysis and assessment by numerical, statistical and constrained based methods in particular to the problems of breach modelling and flood water mitigation.

    Summary

    1 Introduction

    1.1 Background

    1.2 Management of the flood risk caused by structural failure

    1.3 Scope of the thesis

    1.4 Outline of the thesis

    2 Water Retention and Flood Defence Structures

    2.1 Design criteria and failure modes for dams

    2.2 Design criteria and failure modes for dikes

    2.3 Breach modelling

    2.3.1 Breach shape

    2.3.2 Breach development

    2.3.3 Breach formation mechanisms

    2.3.4 Hydraulics of the breaching flow

    3 Current Approaches for Dealing with Flooding

    3.1 Introduction

    3.2 The Netherlands long history of battle against floods

    3.3 Japan’s experience in dealing with floods

    3.4 Modelling of propagation of flood caused by structure failure

    3.5 Uncertainty associated with flood modelling

    4 Current Approaches to Structure Breach Modelling

    4.1 Background

    4.2 Experimental work

    4.3 Empirical equations

    4.4 Physically based models

    5 Data Mining Techniques in Dam Breach Modelling

    5.1 Introduction

    5.2 Main principles of data mining modelling

    5.2.1 Linear regression

    5.2.2 Artificial Neural Networks

    5.2.3 Instance Based Learning (IBL)

    5.3 Application

    5.3.1 Data preparation and model evaluation

    5.3.2 Predicting breach width based on water depth behind the dam

    5.3.3 Predicting peak outflow

    5.4 Conclusions

    6 BREADA model: Breach model for earthfill dams

    6.1 Development of a Dam Breach Model

    6.2 Trapezoidal Shape

    6.3 Validation of the BREADA model

    6.4 Hypothetical dam break analysis of an earthfill dam

    6.4.1 Modelling of breach development

    6.4.2 Modelling of flood propagation

    6.5 Uncertainty in the dam break analysis

    6.6 Discussion and conclusions

    7 Development of a Numerical-Constraint based Model

    7.1 Introduction

    7.2 Methodology

    7.3 Application

    7.4 Discussion and Conclusion

    8 Conclusions and Recommendations

    8.1 Conclusions

    Biography

    Migena Zagonjolli