考虑时效损伤的岩石非线性蠕变模型研究  

Study of Nonlinear Creep Model for Rocks Considering Time-Dependent Damage

作　　者：李忠君 盛冬发 程旭 王怡楠 LI Zhongjun;SHENG Dongfa;CHENG Xu;WANG Yinan(Civil Engineering Institute,Southwest Forestry University,Kunming 650224,Yunnan,China)

机构地区：[1]西南林业大学土木工程学院,云南昆明650224

出　　处：《力学季刊》2022年第4期835-843,共9页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金(11862023);云南省教育厅科学研究基金(2022Y607)。

摘　　要：岩石在高水平应力作用下,其内部损伤随着时间推移不断累积,蠕变呈现出明显的非线性,而传统线性元件组合模型难以描述岩石加速阶段的蠕变行为.为了更好地描述岩石非线性蠕变特征,在传统西原模型基础上引入非线性损伤体,得到改进的西原模型,并推导了该模型的三维蠕变方程.基于Origin平台的LevenbergMarquardt算法,采用泥岩三轴压缩蠕变试验数据对改进西原模型进行拟合,反演得到蠕变模型参数.拟合结果表明:与传统西原模型相比,改进西原模型拟合结果与试验数据具有更高的拟合度,相关系数均在0.96以上,能全面反映岩石非线性蠕变特征,验证了改进西原模型的合理性和适用性.Under the action of high-stress levels, the internal damage of rocks accumulates with time, and the creep behavior shows evident nonlinearity. It is difficult for the traditional linear element combination model to describe the creep characteristics of the rock acceleration stage. In order to better describe the nonlinear creep characterization of rocks, a modified Nishihara model was obtained by introducing a nonlinear damage body based on the traditional Nishihara model, and the three-dimensional creep equations of the model were derived. Based on the Levenberg-Marquardt algorithm of Origin platform, the triaxial compression creep data of mudstone are used to fit the modified Nishihara model and deduce the model’s parameters. The fitting results show that the modified Nishihara model can generate a higher degree of fitting with the test data, with the corresponding correlation coefficients above 0.96. These results indicate that the modified model can comprehensively describe the nonlinear creep characteristics of rocks, verifying the rationality and applicability of the modified Nishihara model.

关 键 词：岩石 损伤演化方程 非线性 加速蠕变 改进西原模型 

分 类 号：TU452[建筑科学—岩土工程]