Coupled Hydro-Mechanical Model of Bentonite Hydration and Swelling

World Multidisciplinary Earth Sciences Symposium 2016

Hancilova, Ilona^1 ; Hokr, Milan^1

Institute for Nanomaterials, Advanced Technology and Innovation, Technical University of Liberec, Czech Republic^1

关键词: Coupled hydro mechanicals;    Effective young's modulus;    Fracture displacement;    Mechanical behaviour;    Non-linear solutions;    Nonlinear diffusion;    Spent nuclear fuels;    Stress deformations;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/44/3/032024/pdf
DOI  :  10.1088/1755-1315/44/3/032024

来源: IOP

【 摘 要 】

This paper deals with the modelling of coupled hydro-mechanical processes at the buffer and host rock interface (bentonite and granite) in the context of the safe disposal of spent nuclear fuel. Granite, as one of the barriers, includes fractures which are the source for hydration of bentonite and its subsequent swelling. It affects the mechanical behaviour and possibly the stability of the whole system. A non-linear solution for the stress-deformation problem with swelling was developed. This solution is coupled with the non-linear diffusion problem (for unsaturated flow). The swelling is defined using a coefficient dependent on water content according to literature data, with the effective Young's modulus decreasing close to zero corresponding to the plastic state. Results confirm the expected non-uniform saturation, swelling, and stresses in bentonite and small contribution to a fracture displacement.