关键词: 岩石损伤, 分区破裂, 应变率效应, 掘进开挖, 损伤本构模型

Abstract: The generation of zonal disintegration of surrounding rock is analyzed by using the numerical simulation software ANSYS/LS-DYNA. Piecewise linear elastoplastic model is used to fit the rock's total stress-strain curve. The excavation of roadways is regarded as a dynamic process by using Cowper-symonds constitutive model in combination with GISSMO model, which take the effects of strain rate and damage on mechanical properties of rock into consideration in mesoscopic scale. Meanwhile, the mechanical properties of rock under various stress conditions are depicted more accurately based on stress triaxiality. The element failure criteria are developed based on maximum strain criterion and maximum tensile stress criterion. The complete stress-strain curve obtained by numerical simulation of uniaxial compression of rock shows good fitting results. According to previous work and engineering practice, the model is modified, and the tunneling and excavation method is adopted in the simulation. The tunneling excavation rate has an impact on the zonal disintegration. Comparison between simulation results and actual observation data demonstrates that the two are consistent.

Key words: rock damage, zonal disintegration, strain rate effect, tunneling excavation, damage constitutive model