Журнал гражданской и экологической инженерии

A Constitutive Model of Sandstone

Abstract

Sitesh Singh

It is extremely challenging to describe the time dependent behaviour of sandstone under stress due to its homogeneity at the macro scale and heterogeneity at the macro scale. Crack initiation and progression may be affected by macro scale heterogeneity. The development of macro scale fractures is strongly influenced by crack clusters. A time-dependent damage model is presented in this paper to investigate the effect of crack evolution on the occurrence of fractures during creep deformation. Based on the elastoplastic theory of rock and the micro-heterogeneous characteristics of sandstone, the instantaneous elastoplastic damage model of sandstone was initially developed. The Nishihara model and the elastoplastic damage constitutive model were combined to create a viscoelastic plastic creep damage model. The outcomes of the corresponding analytical solutions have confirmed the proposed models. The time-dependent behaviour of sandstone was examined using conventional constant strain rate tests and multi-step creep tests to support the model. Both the time-dependent viscoelastic deformation characteristics of sandstone and the creep behaviour’s viscoelastic plastic deformation characteristics are well-represented by the proposed damage model, as demonstrated by the findings.