This book provides a comprehensive text on the geotechnical and geological aspects of the investigations for and the design and construction of new dams and the review and assessment of existing dams. The book provides dam engineers and geologists with a practical approach, and gives university students an insight into the subject of dam engineering. All phases of investigation, design and construction are covered, through to the preliminary and detailed design phases and ultimately the construction phase. This revised and expanded 2nd edition includes a lengthy new chapter on the assessment of the likelihood of failure of dams by internal erosion and piping.

Robin Fell is Emeritus Professor of Civil Engineering at the University of New South Wales, Australia, and also works as a consultant. He has more than 40 years of experience in geotechnical engineering of dams, landslides and civil and mining projects in Australia and Asia. He has worked on over 100 dams worldwide and has been involved in all aspects of planning, site investigation, design and construction of embankment dams.

Patrick MacGregor is a Consulting Engineering Geologist with more than 40 years experience in the assessment of geological constraints for major civil engineering projects in a number of countries. He has been involved in dam investigation, design and construction, and particularly worked on hydroelectric developments at all stages from inception to operation.

David Stapledon spent many years investigating large dam construction sites in various countries. He was a Professor of Engineering Geology at the University of South Australia (1964 -1993) and worked as a Consultant in Engineering Geology, contributing to major dam projects in Australia, New Zealand and South East Asia. He has more than 50 years of experience and was awarded the John Jaeger Memorial Medal for Contributions to Geomechanics in 1995.

Graeme Bell has been a Consulting Dam Engineer since 1962. His role has varied from providing the full technical input, design management and construction advice for new dams to the preparation of complex structural analyses of existing dams. From 1979, he has acted as an independent reviewer on many dam projects, mainly in Australia, but also in several overseas locations.

Mark Foster has 20 years of experience in dam engineering and geotechnical engineering. This has involved a wide variety of projects including dam safety reviews, design of dam upgrade projects and dam safety risk assessments for embankment and concrete dams. He has a particular interest in the assessment of piping and internal erosion of embankment dams which was the topic of his doctoral research studies at the University of New South Wales.

Geotechnical Engineering of Dams, 2nd edition provides a comprehensive text on the geotechnical and geological aspects of the investigations for and the design and construction of new dams and the review and assessment of existing dams. The main emphasis of this work is on embankment dams, but much of the text, particularly those parts related to geology, can be used for concrete gravity and arch dams.

All phases of investigation, design and construction are covered. Detailed descriptions are given from the initial site assessment and site investigation program through to the preliminary and detailed design phases and, ultimately, the construction phase. The assessment of existing dams, including the analysis of risks posed by those dams, is also discussed. This wholly revised and significantly expanded 2nd edition includes a lengthy new appendix on the assessment of the likelihood of failure of dams by internal erosion and piping.

This valuable source on dam engineering incorporates the 200+ years of collective experience of the authors in the subject area. Design methods are presented in combination with their theoretical basis, to enable the reader to develop a proper understanding of the possibilities and limitations of a method. For its practical, well-founded approach, this work can serve as a useful guide for professional dam engineers and engineering geologists and as a textbook for university students.

Author Biographies

1 Introduction 1.1 Outline of the book 1.2 Types of embankment dams and their main features 1.3 Types of concrete dams and their main features

2 Key geological issues 2.1 Basic definitions 2.2 Types of anisotropic fabrics 2.3 Defects in rock masses 2.3.1 Joints 2.3.2 Sheared and crushed zones (faults) 2.3.3 Soil infill seams (or just infill seams) 2.3.4 Extremely weathered (or altered) seams 2.3.5 The importance of using the above terms to describe defects in rock 2.4 Defects in soil masses 2.5 Stresses in rock masses 2.5.1 Probable source of high horizontal stresses 2.5.2 Stress relief effects in natural rock exposures 2.5.3 Effects in claystones and shales 2.5.4 Special effects in valleys 2.5.5 Rock movements in excavations 2.6 Weathering of rocks 2.6.1 Mechanical weathering 2.6.2 Chemical decomposition 2.6.3 Chemical weathering 2.6.3.1 Susceptibility of common minerals to chemical weathering 2.6.3.2 Susceptibility of rock substances to chemical weathering 2.6.4 Weathered rock profiles and their development 2.6.4.1 Climate and vegetation 2.6.4.2 Rock substance types and defect types and pattern 2.6.4.3 Time and erosion 2.6.4.4 Groundwater and topography 2.6.4.5 Features of weathered profiles near valley floors 2.6.5 Complications due to cementation 2.7 Chemical alteration 2.8 Classification of weathered rock 2.8.1 Recommended system for classification of weathered rock substance 2.8.2 Limitations on classification systems for weathered rock 2.9 Rapid weathering 2.9.1 Slaking of mudrocks 2.9.2 Crystal growth in pores 2.9.3 Expansion of secondary minerals 2.9.4 Oxidation of sulphide minerals 2.9.4.1 Sulphide oxidation effects in rockfill dams - some examples 2.9.4.2 Possible effects of sulphide oxidation in rockfill dams 2.9.4.3 Sulphide oxidation - implications for site studies 2.9.5 Rapid solution 2.9.6 Surface fretting due to electro-static moisture absorption 2.10 Landsliding at dam sites 2.10.1 First-time and "reactivated'' slides 2.10.1.1 Reactivated slides 2.10.1.2 First-time slides 2.10.2 Importance of early recognition of evidence of past slope instability at dam sites 2.10.3 Dams and landslides: Some experiences 2.10.3.1 Talbingo Dam 2.10.3.2 Tooma Dam 2.10.3.3 Wungong Dam 2.10.3.4 Sugarloaf Dam 2.10.3.5 Thomson Dam 2.11 Stability of slopes around storages 2.11.1 Vital slope stability questions for the feasibility and site selection stages 2.11.1.1 Most vulnerable existing or proposed project features, and parts of storage area? - Question 1 2.11.1.2 Currently active or old dormant landslides? - Questions 2 and 4 to 7 2.11.1.3 Areas where first-time landsliding may be induced (Questions 3 to 7) 2.11.1.4 What is the likely post failure velocity and travel distance? 2.11.1.5 What is the size of impulse waves which may be created? 2.12 Watertightness of storages 2.12.1 Models for watertightness of storages in many areas of non-soluble rocks 2.12.2 Watertightness of storage areas formed by soluble rocks 2.12.3 Features which may form local zones of high leakage, from any storage area 2.12.4 Watertightness of storages underlain by soils 2.12.5 Assessment of watertightness 2.12.5.1 Storages in non-soluble rock areas - assessment of watertightness 2.12.5.2 Storages in soluble rock areas - assessment of watertightness 2.12.5.3 Storages formed in soils - assessment of watertightness 2.12.6 Methods used to prevent or limit leakages from storages

3 Geotechnical questions associated with various geological environments 3.1 Granitic rocks 3.1.1 Fresh granitic rocks, properties and uses 3…