基于加速蠕变改进的巷道围岩蠕变模型

An improved creep model of roadway surrounding rock based on accelerated creep

为了研究流固耦合在岩石蠕变过程中的作用机制,利用MTS815. 02岩石力学试验系统,对巷道围岩(砂岩)开展蠕变试验,研究岩石在蠕变过程中的变形破坏特性,基于加速蠕变改进的蠕变模型来描述蠕变过程,采用最小二乘法识别蠕变参数,分析蠕变参数随应力和时间的变化过程;将自定义蠕变方程嵌入ANSYS有限元软件,数值模拟了饱和砂岩试样的流固耦合蠕变全过程。结果表明:该蠕变模型可以较好地描述岩石蠕变全过程;数值模拟结果与试验结果吻合,验证了该蠕变模型和蠕变参数随时间变化规律的正确性和合理性,可为深部工程的隧道围岩加固、灾害防治和支护设计提供依据。

In order to study the mechanism of fluid-structure interaction in rock creep process,the creep experiment of roadway urrounding rock(sandstone) by MTS815. 02 rock mechanics test system was carried out,and the deformation and failure properties of rock during creep were studied. The creep process was described based on the improved creep model of accelerated creep. The least squares method was used to identify creep parameters,and the changes of creep parameters with stress and time were analyzed. Then the self-defined creep equation was embedded into the ANSYS finite element software to simulate the whole process of fluid-structure interaction creep of saturated sandstone samples.The results show that the proposed creep model can describe the whole creep process of rock well,that the good fit between the numerical simulation results and the experimental curves indicates that the model can better describe the accelerated creep properties of rocks,that the correctness and rationality of creep model and creep parameters with time are verified,and that the model provides the basis for reinforcement,disaster prevention and support design of roadway surrounding rock in deep engineering.