Page 8 - Engineering Rock Mass Classification_ Tunnelling, Foundations and Landslides

Contents

Preface xiii
Acknowledgments xv

1. Philosophy of Engineering Classifications 1

The Classification 1
Philosophy of Classification System 2
Need for Engineering Geological Map 2
Management of Uncertainties 3
Present-Day Practice 3
Scope of the Book 4

2. Shear Zone Treatment in Tunnels and Foundations 7

Shear Zone 7
Treatment for Tunnels 7
Treatment for Dam Foundations 9

3. Rock Material 13

Rock Material 13
Homogeneity and Inhomogeneity 13
Classification of Rock Material 13
Class I and II Brittle Rocks 15
Uniaxial Compression 16
Stability in Water 17
Classification on the Basis of Slake Durability Index 18

4. Rock Quality Designation 21

Rock Quality Designation 21
Direct Method 21
Indirect Methods 23
Weighted Joint Density 24
Red-Flag Effect of Low RQD 29
Application of RQD 30

5. Terzaghi’s Rock Load Theory 33

Introduction 33
Rock Classes 33
Rock Load Factor 33
Modified Terzaghi’s Theory for Tunnels and Caverns 42

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