基于PFC^(3D)的加权平均数建模法在三轴数值试验中的应用

Weighted Average Assembling Method Using in Triaxial Numerical Experiment Based on PFC^(3D)

基于室内三轴试验研究成果,以PFC^(3D)为工具建立三维颗粒流模型,开展三轴数值试验研究.针对大型三轴数值试验大范围粒径颗粒生成困难问题,提出了加权平均数数值建模方法,并以转动颗粒场分析手段为依据进行局部裂隙细观分析.研究表明,加权平均数数值建模法得到的颗粒级配与室内试验颗粒级配及三轴试验结果吻合度都较好,此法有利于提高计算效率;转动颗粒场有利于三维立体模型剪切面的细观分析,将其与颗粒位移场相结合进行细观分析能更好的揭示粗粒土宏观力学及变形特性的内在机制.

Based on the results of indoor triaxial experimental research, a three-dimensional particle flow model is established based on PFC3D to conduct triaxial numerical experiments. Based on the problem of a wide range of particle size in large-scale triaxial numerical test, numerical modeling method of weighted average assembling is proposed. Based on the analysis method of rotating particles field, local fracture microstructure analysis has been conducted. The results show that the particle gradations from laboratory agree well with the simulation results generated by weighted average generate method. In addition, the results of macro responses have great agreement. This method is bene-ficial to improving the calculation efficiency. Besides, the field of rotating particles in the shear meso-scopic analysis of three-dimensional model is advantageous. By combining the displacement field, the particle mesoscopic analysis can better reveal the internal mechanism of mechanics and deformation characteristics of coarse grained soil.