Modeling gravity hazards from rockfalls to landslides / Vincent Richefeu and Pascal Villard.

Format:

Book

Author/Creator:

Richefeu, Vincent, author.

Villard, Pascal, author.

Series:

Discrete granular mechanics set

Language:

English

Subjects (All):

Landslide hazard analysis.

Landslides--Mathematical models.

Landslides.

Slopes (Soil mechanics)--Mathematical models.

Slopes (Soil mechanics).

Geological modeling.

Physical Description:

xvi, 161 pages : illustrations ; 24 cm.

Place of Publication:

London : ISTE Press Ltd ; Kidlington, Oxford : Elsevier Ltd, [2016]

Summary:

Gravity hazards are a major concern to those living in mountainous areas. To protect infrastructure and human life in these areas, engineers require numerical tools for trajectory analysis, for application from fragmental rockfalls to large-scale avalanches or landslides. This book explores state-of-the-art methods to model the propagation (flows and stops) of masses, using the discrete element method (DEM) to study the evolution of kinetics during an event. Taking into account the shape of the blocks and the topology of the terrain provides an explicit and sophisticated consideration of geometries, eliminating the need for stochastic inputs to rockfall simulations. This method is validated experimentally, before the authors apply it to real case studies. The book ends with an introduction to and comparison with the material point method (MPM), a new and promising approach able to bridge the gap between cases dominated by discreteness and those involving a very large number of elements. Engineering consulting firms, researchers and students should find the approaches outlined in this book useful, whether designing prevention and protection systems for gravity hazards, or exploring new ways to model gravity hazards. Book jacket.

Contents:

Chapter 1 Computational Methods 1

1.1 Trajectory analysis 1

1.2 Discrete element method 3

1.2.1 Block shapes 3

1.2.2 Mass properties 5

1.2.3 Block motions 7

1.2.4 Pre-existing discontinuities 10

1.2.5 Digital terrain model 12

1.2.6 Contact force laws 13

1.2.7 Neighborhood of each block 19

1.3 Material point method 21

1.3.1 Conservation equations 23

1.3.2 Discretization and continuity relations 24

1.3.3 Explicit time integration 27

1.3.4 Stability 30

1.3.5 Constitutive model 33

Chapter 2 DEM Applied to Laboratory Experiments 37

2.1 Description of the experiments 38

2.1.1 2D releases within a channel 38

2.1.2 3D releases on a two-side slope 39

2.2 Definition and assessment of the contact parameters 41

2.2.1 2D releases 41

2.2.2 3D releases 42

2.3 Simulation versus experiment results 46

2.3.1 2D releases 46

2.3.2 3D releases 51

2.4 Further clues handled by numerical results 55

2.4.1 Dissipation modes 56

2.4.2 Kinematics 60

2.5 Concluding remarks 61

Chapter 3 Parameters that May Affect the Flow 63

3.1 Constituting blocks 63

3.1.1 Amount 63

3.1.2 Shapes 72

3.2 Contact parameters 77

3.3 Propagation area 83

3.3.1 Abrupt change in slope 83

3.3.2 Relative roughness 89

3.4 Concluding remarks 100

Chapter 4 Application to Actual Rockfalls 103

4.1 Retro analysis of a natural rockfall implying a few blocks 103

4.1.1 Purpose of the modeling 103

4.1.2 Description of the event 104

4.1.3 Numerical model and parameters 107

4.1.4 Selected results 109

4.2 Numerical modeling of an artificially triggered rockfall 116

4.2.1 Purpose of the modeling 116

4.2.2 Description of the site 117

4.2.3 Numerical model and parameters 121

4.2.4 Selected results 122

4.3 Forecast of a rockfall propagation toward a protective structure 126

4.3.1 Purpose of the modeling 126

4.3.2 Description of the natural site 126

4.3.3 Numerical model and parameters 129

4.3.4 Selected results 129

Chapter 5 From Discrete to Continuum Modeling 135

5.1 Geometries and parameters used 135

5.2 Analysis 138

5.2.1 Relatively low friction at the base 139

5.2.2 A higher friction at the base 143

5.2.3 Sensitivity to the internal friction 146

5.3 Concluding remarks 148.

Notes:

Includes bibliographical references (pages 153-157) and index.

ISBN:

1785480766

9781785480768

OCLC:

947145374