围岩卸载损伤演化及应力场调整有限元分析

Finite Element Analysis on Damage Progress by the Unloading of Surrounding Rock and Stress Field Regulation

隧道、洞室等地下工程的修建过程 ,是洞室壁面附近围岩不断发生应力卸载的过程。在这一过程中围岩力学性质与加载过程中表现出的力学性质存在一定的差别。本文通过引入服从韦伯分布函数的细观岩石微元体 ,运用连续介质损伤力学理论 ,得出了可以反映岩石非均匀性的本构关系式 :然后运用岩石破裂与失稳过程RFPA分析系统 ,对隧道、洞室等地下工程由于洞室开挖引起的围岩卸载过程中 ,洞室孔壁附近围岩发生的损伤演化和应力场调整全过程进行了有限元分析 ,得到了洞室壁面附近围岩损伤演化和应力场调整过程图。

In this paper by introducing the rock micro unit conforming to Weber distribution function, using the theory of damage mechanics of continuous media, a formula of constitutive relationship expressing the heterogeneity of the rock is obtained. Then, using the RFPA analytical system for the rock disruption and destabilizing process, a finite element analysis was carried out on the whole process of damage progress and stress field regulation occurred at rock near the tunnel wall surface during unloading of the rock due to tunnel excavation in underground projects such as tunnel cavern etc. A diagram of the process of rock damage progress and regulation of stress field regulation has been obtained.