Thermo-hydro-chemical coupling

All these processes are the product of a system driven by the Earth s climate and characterised by strong thermo-hydro-mechanical coupling, in which both chemical processes and transient phenomena are important. 

The coupling effects of various poromechanical processes on the response of a porous medium have been successfully addressed by Biot s theory of poroelasticity and its extensions [3,4,5,8,2], The chemical effects have also been addressed by considering interaction between the porous matrix and a pore fluid comprising of a solute and solvent [10, 7, 6], Comprehensive anisotropic poromechanics formulations and corresponding solutions for the inclined borehole problem have been presented [4—2], However, the coupled chemo-thermo-hydro-mechanical response of an anisotropic porous medium has not been addressed to date. 

In this paper, the focus is on the development of a poromechanics model which addresses the chemical effects within the framework of the anisotropic porothermoelastic model [2], The resulting model, termed as porochemo-thermoelastic, accounts for fully coupled chemo-thermo-hydro-mechanical response of a chemically active formation saturated with a pore fluid comprising of two species under non-isothermal conditions. The numerical example presented demonstrates the thermo-chemical effect on the stress and pore pres-... 

A RESEARCH PROGRAM FOR NUMERICAL EXPERIMENTS ON THE COUPLED THERMO-HYDRO-MECHANICAL AND CHEMICAL PROCESSES IN THE NEAR-FIELD OF A HIGH-LEVEL RADIOACTIVE WASTE REPOSITORY... 

Abstract In the near-field of a high-level radioactive waste (HLW) repository, the coupled thermo -hydro -mechanical and chemical (T-H-M-C) processes will occur. Observation periods by laboratory and in-situ experiments are very short and information by natural analogue studies is very limited, so numerical experiments are the only available approach to predict the near-field long-term evolution. We have initiated a research on the coupled T-H-M-C processes and are trying to carry out numerical experiments on the coupled T-H-M-C processes in order to predict the near-field long-term evolution. This paper presents our current status and future activities on the research for numerical experiments on the coupled T-H-M-C processes. 

In the near-field of a HLW repository, the coupled thermo -hydro -mechanical and chemical (T-H-M-C) processes will occur, involving the interactive processes among radioactive decay heat from the vitrified waste, infiltration of groundwater into bentonite, swelling pressure of bentonite due... 

Our activities on development of the coupled T-H-M-C code and further demonstration analysis are presented by Neyama et al. in GeoProc 2003 conference, entitled Prototype Code Development for Numerical Experiments on the Coupled Thermo-Hydro-Mechanical and Chemical Processes in the Near-field of a High-level Radioactive Waste Repository . The prototype code is based on the coupled T-H-M code, mass transport code and geochemical code which have been well verified and validated through benchmark tests and various experiments, and... 

Japan Nuclear Cycle Development Institute (JNC) has already developed the coupled thermo -hydro and mechanical (T-H-M) model and has initiated a research on the coupled T-H-M-C processes to predict the chemical evolution of buffer material and porewater chemistry, and the chemical effects on other (thermal, hydraulic and mechanical) processes. In this research, numerical experiment system for the coupled T-H-M-C processes is developed in order to predict the longterm evolution of the near-field (engineered barriers and surrounding host rock) for various repository designs and geological environments. 

COUPLED THERMO HYDRO MECHANICAL-CHEMICAL PROCESSES IN GEO-SYSTEMS... 

Coupled Thermo-Hydro-Mechanical-Chemical Processes in Geo-Systems... 

I am pleased to be able to introduce this book on Coupled thermo-hydro-mechanical-chemical processes in geo-systems fundamentals, modelling, experiments and applications as the second publication in the Elsevier Geo-Engineering Book Series. The book contains the proceedings of the GeoProc2003 conference held at the Royal Institute of Technology in Stockholm, Sweden, in October 2003. 

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