A Numerical Study Of Rock Mass Progressive Failure Based On General Particle Dynamics

The stability of rock engineering which influenced by the complex stress conditions,Meshless method is capable of dealing with the problem of progressive failure, It is pop method of research for the numerical method in geotechnical engineering. Based on the previous research work of meshless method, General Particle Dynamics(GPD) method is proposed to apply to geotechnical engineering. The main works and research findings are written as following:① A novel meshless general particle dynamics(GPD3D) method, which base on conservation equation of solid, is proposed in this paper to simulate the failure process of rock. An elasto-brittle damage model based on the Mohr-Coulomb criterion is applied to reflect the initiation, growth and coalescence of cracks and the macro-failure of slopes. The Weibull statistical approach is applied to model the heterogeneity of geomaterials.② GPD method is used to simulate the failure process of 2D and 3D samples subjected to uniaxial compressive loads. Several macro-fracture modes of samples subjected to uniaxial compressive loads are modeled due to the heterogeneity of geomaterials.③ SRM(Shear strength reduction method) is implemented in the GPD method. A simple approach is proposed to define the safety factor using the GPD method to analyze stability of slope.④ The geomaterial-structure(reinforcing pile) interaction is simulated as an elastic-perfectly materials. As an application of GPD to slopes, the interaction between the slopes and the reinforcing pile is simulated, and the proposed geomaterial-structure interaction algorithm works well in the framework of GPD method.⑤ Non-associated flow law and associated flow law can be applied to analyze the plastic deformation of the surrounding rock masses around tunnels using GPD method. The stability of the surrounding rock masses around tunnels are also determined using General Particle Dynamics(GPD) method as well as the stress fields, displacement fields and plastic zone. It is proved that GPD method is efficient to predict the elastic-plastic properties of the surrounding rock masses around tunnels.⑥ Based on the mechanical state of “the high geostress+the dynamic disturbance”, HJC(Holmquist-Johnson-Cook) rate dependent model is adoped in the circular tunnel with several different pre-existing flaws, GPD method with HJC model can be applied to simulate rockurst.⑦ The tunnels at the Jingping II Hydropower Station in Sichuan serving as research background,stability of the tunnels have been analyzed with theoretical analysis,numerical simulation and model test.