从修正的Drucker公设和本构关系的内变量理论出发,对一般形式的含损伤粘塑性屈服模型导出了增量型本构关系的一般形式,并对岩土介质中常用的率形式Mohr-Coulomb模型给出了其本构增量算法的具体形式。所提出的增量本构关系是由增量应变表达增量应力的显式形式,故特别适用于高速冲击等动态力学问题。作为算例,该文以所提出的增量本构关系为基础,开展了岩石平板撞击层裂问题的数值模拟,结果良好。
Based on the modified Drucker’s postulate and the internal variables theory of constitutive relations,the general incremental constitutive relations for the general viscoplastic yield models of damaged materials are deduced, and the pertinent strict incremental constitutive algorithm for Mohr-Coulomb model with strain-rate effect, which is often used in rock and soil mechanics, are obtained. The presented strict incremental algorithm is an explicit form with the incremental stress calculated by increment strain, which is particularly convenient and applicable to high velocity impact problems. As an example, the computational simulation for the problem of spallation caused by the impact of two rock slabs is carried out. Based on the presented increment constitutive algorithm, the results are satisfactory.