基于温度损伤的红砂岩本构模型

A Constitutive Model of Red Sandstone Based on Temperature Damage

摘要: 本文针对深部地下岩体工程中岩石处于高温环境，且所处的三向应力状态一般为σ1 > σ2 > σ3。考虑了岩石高温下的损伤和真三轴应力条件下的岩石的应力损伤。基于Lemaitre应变等效假设理论，通过引入能够反映岩石在热力耦合条件下的温度损伤变量和力损伤变量来描述岩石材料的损伤程度，根据热力耦合损伤变量的指数分解形式引入热力耦合损伤变量，基于D-P准则建立岩石高温–荷载耦合损伤的真三轴瞬时本构模型。

Abstract: This study focuses on the high-temperature environment encountered in deep underground rock engineering, where the triaxial stress state is generally σ1 > σ2 > σ3. Considering both the damage to rocks under high temperatures and the stress damage under true triaxial stress conditions, based on Lemaitre’s strain equivalence hypothesis theory, the temperature damage variable and mechanical damage variable, which can reflect the damage degree of rock materials under thermo-mechanical coupling conditions, are introduced to describe the damage extent of rock materials. The thermo-mechanical coupling damage variable is introduced according to the exponential decomposition form of the thermo-mechanical coupling damage variable. True triaxial instantaneous constitutive models for high temperature and load coupling damage of rocks are established based on the D-P criterion.