Sulphatic claystones are among the most problematic rocks in tunnelling due to their distinctive swelling properties. They are known to have caused severe damage, for example, to numerous tunnels excavated in the Gypsum Keuper formation. The repairs were extremely costly and time-consuming, and often provided only a temporary solution. The setbacks experienced in tunnelling through Gypsum Keuper may be attributed, among other things, to our limited knowledge of the macroscopic principles governing the swelling process and the underlying microscopic mechanisms.
The issues in question have formed the focal point of long-standing research in the Chair of Underground Construction at ETH Zurich. A series of theoretical and experimental research projects are being conducted to investigate the interactions between chemical reactions, transport processes and the observed macroscopic behaviour. The objective of the investigations is to improve our understanding of swelling processes in order to yield a scientifically established basis for design. This work has achieved important progress towards this objective. It has systematically and comprehensively analysed the thermodynamics and the kinetics of the chemical reactions involved in the swelling process, as well as their interplay with advective and diffusive ion transport. The topic is of great value in terms of further investigation in this area.
Reihe
Sprache
Verlagsort
Zielgruppe
Für höhere Schule und Studium
Für Beruf und Forschung
Dateigröße
ISBN-13
978-3-7281-3647-3 (9783728136473)
Schweitzer Klassifikation
1 - Cover [Seite 1]
2 - Imprint [Seite 3]
3 - Preface [Seite 4]
4 - Vorwort [Seite 6]
5 - Acknowledgements [Seite 8]
6 - Abstract [Seite 10]
7 - Zusammenfassung [Seite 14]
8 - Table of contents [Seite 20]
9 - 1 Introduction [Seite 24]
9.1 - 1.1 Tunnelling in swelling rocks [Seite 24]
9.2 - 1.2 State of research [Seite 24]
9.3 - 1.3 Objectives and structure of the dissertation [Seite 29]
10 - 2 Thermodynamic Fundamentals [Seite 32]
10.1 - 2.1 Introduction [Seite 32]
10.2 - 2.2 Basic thermodynamic relations [Seite 35]
10.3 - 2.3 Equilibrium concentrations [Seite 47]
10.4 - 2.4 Gypsum-Anhydrite equilibrium relationships [Seite 48]
10.5 - 2.5 Comparison between predicted solubilities and published data [Seite 50]
10.6 - 2.6 Comparison of predicted equilibrium conditions with published data [Seite 51]
10.7 - 2.7 General equilibrium diagram [Seite 55]
10.8 - 2.8 Conclusions [Seite 56]
11 - 3 Anhydrite in Gypsum Keuper at Shallow Depths [Seite 58]
11.1 - 3.1 Introduction [Seite 58]
11.2 - 3.2 The small pore hypothesis [Seite 64]
11.3 - 3.3 The high pressure hypothesis [Seite 68]
11.4 - 3.4 The low water activity hypothesis [Seite 93]
11.5 - 3.5 Conclusions [Seite 97]
12 - 4 Maximum Swelling Pressure of Anhydritic Claystones [Seite 100]
12.1 - 4.1 Introduction [Seite 100]
12.2 - 4.2 Microscale [Seite 102]
12.3 - 4.3 Macroscale [Seite 112]
12.4 - 4.4 Megascale [Seite 130]
12.5 - 4.5 Conclusions [Seite 136]
13 - 5 Time Development of Sulphate Hydration [Seite 138]
13.1 - 5.1 Introduction [Seite 138]
13.2 - 5.2 Kinetic model [Seite 139]
13.3 - 5.3 Comparison of predictions with tests involving simultaneous anhydrite dissolution and gypsum precipitation [Seite 154]
13.4 - 5.4 Factors governing the time development of hydration [Seite 157]
13.5 - 5.5 The effect of sealing [Seite 164]
13.6 - 5.6 Conclusions [Seite 168]
14 - 6 On the Role of Transport Processes [Seite 170]
14.1 - 6.1 Introduction [Seite 170]
14.2 - 6.2 Governing equations of the advection-diffusion model [Seite 172]
14.3 - 6.3 Model behaviour [Seite 176]
14.4 - 6.4 The role of diffusion in oedometer tests [Seite 183]
14.5 - 6.5 The role of advection [Seite 189]
14.6 - 6.6 Conclusions [Seite 192]
15 - 7 Conclusions and Outlook [Seite 194]
16 - Appendix A. Closed-form solutions for cavity expansion [Seite 196]
17 - Appendix B. Effect of oedometer stiffness [Seite 206]
18 - Appendix C. Derivation of Flückiger et al. (1994) [Seite 208]
19 - Appendix D. Reaction rates [Seite 210]
20 - Appendix E. Volume fraction [Seite 214]
21 - Appendix F. Notation [Seite 216]
22 - References [Seite 228]
