论文部分内容阅读
针对目前常规数值计算方法的局限,该文采用一种纯拉格朗日、无网格方法——光滑粒子流体动力学法(简称SPH法)对土体的大变形力学行为进行数值模拟。首先,根据SPH法的基本理论,对弹塑性力学控制方程进行了离散,构造了应力-应变关系的SPH求解格式,并采用Jaumann应力率进行土体应力-应变与内部质点运动间的转换。然后,进行两组数值模拟试验:1)对弹性体大变形单剪试验进行数值模拟,与解析解进行比较;2)对采用修正剑桥模型的土体大变形不排水单剪试验进行数值模拟,并与有限元程序的大变形单剪试验计算结果进行比较。结果表明:SPH数值模拟方法具有较好的稳定性和计算精度,从而实现了这种新型计算方法在土体大变形弹塑性数值模拟研究中的成功应用。
Aiming at the limitations of the current numerical methods, a pure Lagrangian and meshless method, smooth particle hydrodynamics (SPH), is used to simulate the large deformation mechanics of soils. First of all, according to the SPH method, the governing equations of elasto-plastic mechanics are discretized and the SPH solution of stress-strain relationship is constructed. The Jaumann stress rate is used to convert the soil stress-strain and the internal particle motion. Then, two numerical simulations are carried out: 1) Numerical simulations of large shear tests on elastomers are carried out and compared with analytical solutions; 2) Numerical simulations of large deformation undrained soil subjected to shear tests using a modified Cambridge model are carried out. And compared with the finite element program of large deformation single shear test results. The results show that the SPH numerical simulation method has good stability and calculation accuracy, and thus the successful application of this new calculation method in large deformation elasto-plastic numerical simulation is realized.