胶凝堆石料力学特性的离散元数值模拟研究

Discrete Element Numerical Simulation Study on Mechanical Properties of Cemented Sand and Gravel

利用离散元方法对胶凝堆石料力学特性进行了数值模拟研究。针对胶凝堆石料的属性,对黏结模型进行了特殊赋值,得到了与室内试验一致的数值模拟结果,分析胶凝强度对该材料偏应力峰值、内摩擦角的影响,进一步通过胶凝堆石料和无黏结材料的对比,研究了偏应力、体应变的变化规律。结果表明:采用离散元方法从细观尺度对颗粒胶凝材料的研究可以作为大三轴室内试验的补充,适用于胶凝材料的机理研究、分析宏-细观参数等因素的影响;模拟过程和结果与试验结果一致;细观接触黏结强度对宏观内摩擦角和黏聚力均有影响,与偏应力峰值强度成指数函数关系。

The numerical simulation of largetriaxial shear tests of CSG material were carried out by the discrete element method. According to the CSG material properties,the special assignment of the bond model was carried out and the numerical simulation results consistent with the laboratory test were shown. The influence of gel strength to the deviatoric stress peak and the internal friction angle of the material were analyzed. Further,the change law of partial stress and body strain were studied by comparing the cementing rockfill with the CSG material. The results show that the discrete element method from meso scale on the particle of cementitious materials can be used as supplementary triaxial test,research and analyze the mechanism for cementitious materials influence the macro meso parameters; simulation process and results can be consistent with the experimental phenomenon; meso contact bond strength of friction angle and cohesion have influence to the macro and partial exponential function with peak stress intensity.