Rheological damage FEA of hydro-mechanical coupling for rock mass

Abstract

There are a large number of random distributing pores and cracks in rock mass, and the initial damages of different causes of formation may be grown with engineering action or changes of all kinds of natural conditions, and the physical and mechanical properties of rock are changed and the structure of rock mass is also changed. At the same time, not only the rock caverns located under groundwater table are subjected to the coupling action of stress field with seepage field, but also the deformation of surrounding rock varies with time. In order to consider these effects in the process of hydro-mechanical coupling, the rheological damage model of hydro-mechanical coupling was set up, based on the fundamental theories of rock mass hydraulics and rheological mechanics and damage mechanics. The according finite element analysis (FEA) formulas for rock mass were derived, and the concretely executive process was given for the FEA of coupled stress field with seepage field under the condition of considering rheological and damage for rock mass. The rheological damage model established may be applied to the long-term stability analysis for underground caverns and slope engineering under the condition of hydro-mechanical coupling.

Keywords

hydro-mechanical coupling / rheology / damage / FEA

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