不同应力差下非线性蠕变研究

Study on Nonlinear creep under the Different Stress Differences

深部工程处于复杂的环境场(应力场、温度场和渗流场)之中,引起的地下工程围岩流变破坏事故屡见不鲜。本文通过三轴蠕变实验,根据岩体流变力学和蠕变原理对影响深部岩体蠕变的因素进行了研究。用实验数据进行数值计算,得出了深部软岩巷道围岩在高地应力作用下的非线性蠕变模型,建立了应力差-时间-蠕变的定量关系,利用MATLAB软件得到了不同情况下的蠕变-时间曲线;应力差-时间-蠕变曲面。从而验证了非线性流变理论,找到了引起蠕变的主要因素应力差。并利用应力差理论分析了深部巷道围岩的蠕变破坏机理。

A deep engineering is under the resultant action of complex environmental fields （such as stress field, temperature field and seepage field）. A lot of accidents take place due to the rheodestruc-tion of surrounding rock in underground engineering. Based on the theories of rock rheology and creep the factors influencing creep of deep rock were studied by triaxial creep-experiments in this paper. The nonlinear creep equation for surrounding rock of soft rock tunnel in deep mining under high ground stresses is obtained by simulating numerically. The quantitative relationship among stress deviation, time and creep is found. The creep-time curves and stress deviation-time-creep surfaces in different cases are gotten by using MATLAB. And then it is confirmed that Stress Difference is the dominant factor of engendering creep, the Theory of Nonlinear Rheology is proved. Finally, creep failure mechanism of surrounding rock in deep mining is analyzed by stress difference theory.