软岩非线性黏弹塑性蠕变模型及参数识别  

Nonlinear viscoelasto-plastic creep model of soft rock and its parameters identification

作　　者：舒志乐[1] 刘保县[1] 黄山[1] 魏于航 赵宝云[2] SHU Zhile LIU Baoxian HUANG Shan WEI Yuhang ZHAO Baoyun(Architectural and Civil Engineering College, Xihua University, Chengdu, Sichuan 610039, China School of Civil Engineering and Architecture, Chongqing University of Science and Technology, Chongqing 401331)

机构地区：[1]西华大学建筑与土木工程学院,四川成都610039 [2]重庆科技学院建筑工程学院,重庆401331

出　　处：《采矿与安全工程学报》2017年第4期803-809,共7页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金创新群体项目(50621403);教育部春晖计划项目(14206503);西华大学重点基金项目(z1120635)

摘　　要：软岩的蠕变具有明显的非线性特征,并且受温度、湿度、荷载类别、应力水平、孔隙水压力等因素影响,在分析应力水平、孔隙水压力对蠕变特性影响的基础上,提出了一个非线性黏滞系数牛顿元件,其黏滞系数是所加应力水平、孔隙水压力和蠕变时间的函数,将非线性黏性模型与西原模型串联,得到一个软岩非线性黏弹塑性蠕变模型,推导了不同恒定荷载情况下的蠕变方程,并分析了模型的非线性特征和参数的敏感性,结果表明,该模型可同时表征软岩蠕变的3个阶段,最后,基于1stOpt软件的通用全局优化算法对模型参数进行了识别,辨识的结果与试验曲线吻合较好,初步表明复合流变模型的适用性和正确性,可为今后开展类似研究提供一定的参考依据。The creeping of soft rock has obvious nonlinear characteristics,and it is affected by such factors as temperature,humidity,load type,stress level,pore water pressure.A non-linear viscosity coefficient Newton element was proposed based on the analysis of the influence of stress level and pore water pressure on the creep characteristics.Its viscosity coefficient is a function of the stress level,the pore water pressure,and the creep time.A nonlinear viscoelastic plastic creep model of soft rock was obtained through the nonlinear viscosity model and the original model in series.A creep equation under different constant loads was derived,and the nonlinear characteristics and sensitivity of the parameters of the model were analyzed.The results have shown that the model can characterize the creep of soft rock at 3 stages.Finally,the model parameters were identified based on the general global optimization algorithm with 1st Opt software,and the identification results are in good agreement with the experimental curves,which has a preliminary indication of the applicability and correctness of the composite rheological model and can provide a reference for future similar studies.

关 键 词：软岩 应力水平 孔隙水压力 参数识别 复合流变模型 

分 类 号：TU458[建筑科学—岩土工程]