Computational Geotechnics (eBook)

Dr. Thomas Nagel leads the "Computational Energy Systems" research group in the Department of Environmental Informatics at the Helmholtz Centre for Environmental Research (UFZ). The Centre studies the complex interactions between humans and the environment in cultivated and damaged landscapes, especially densely populated urban and industrial areas and natural landscapes. The scientists and researchers who work in the Centre develop concepts and processes to help secure the natural foundations of life for future generations.

Preface 6
Acknowledgements 8
Contents 9
About the Authors 10
1 Introduction 12
1.1 Energetic Use of the Subsurface 12
1.2 Geotechnical Use of Rock Salt 13
1.3 Gas Storage in Salt Caverns 14
1.4 Scope and Structure of This Tutorial 16
2 Basics of Thermomechanics and Inelasticity 17
2.1 Governing Equations 17
2.2 Finite Element Implementation and the Kelvin Mapping 20
The Kelvin Mapping of Tensorial Quantities 20
Finite Element Implementation 22
2.3 Integration of Inelastic Constitutive Models 23
General Aspects 23
Integration Algorithm 24
2.4 Thermo-Mechanical Coupling in OGS 26
2.5 Constitutive Models 27
Thermal Process 27
Mechanical Process 27
LUBBY2 28
Minkley 29
Coupling 32
3 Simulation of Laboratory Tests 33
3.1 Non-isothermal Triaxial Creep Test 33
Geometry and Boundary Conditions 34
Material Properties 38
Numerical Settings 40
Time Stepping 41
Output 42
Simulation Results 42
3.2 Triaxial Test with Plasticity 45
Geometry and Boundary Conditions 45
Material Properties 47
Numerics 48
Results 49
4 Simulating Gas Storage in Salt Caverns 54
4.1 Scenario 54
4.2 General Set-Up 56
Cavern Geometry 56
Initial Conditions 57
Boundary Conditions 57
Source Terms 59
Time Discretisation 61
4.3 Isothermal Model Set-Up 62
Material Properties 64
4.4 Non-isothermal Model Set-Up 65
Initial Conditions 65
Boundary Conditions 65
Material Properties 66
4.5 Comparison of Results 66
5 Closing Remarks 72
References 73
Index 77