基于FLAC3D二次开发的含预制缺陷岩体数值模拟

Numerical Simulation of Prefabricated Defects Rock Mass Based on Secondary Development of FLAC3D

为研究不同缺陷角度下双裂纹岩体的强度与破坏特征,利用C++语言对FLAC3D进行二次开发,构建了1种弹脆性损伤本构模型。引入基础单元与破裂单元的概念,将岩石在细观上破坏前的力学行为假定为线弹性,破裂性质假定为弹脆性,当基础单元达到强度准则后转换为破裂单元,其力学参数进行相应的弱化使其承载能力维持在残余强度水平。数值模拟结果表明,随着缺陷角度的增加,岩体强度先下降后上升,而细观破裂由拉伸-剪切型的混合破坏转变为剪切破坏。

To investigate the strength and failure characteristics of double cracked rock mass under different defect angles,C++language is employed to develop an elastic-brittle damage constitutive model inner FLAC3D.The concept of basic unit and rupture unit are pulling into this model.The mechanical behavior of meso rock units before fracture is assumed to be elasticity,and the rupture property is assumed to be elastic brittleness.The basic units are converted into rupture units while the stress state reaches the strength criterion and its mechanical parameters are correspondingly weakened.The mechanics parameters of rupture units maintain at the level of residual strength.The numerical simulation results indicate that the rock mass strength decreases first and then increases with the increase of the defect angle,while the meso-fracture transforms from the tensile-shear mixed failure to the shear failure.