混凝土爆破损伤的SPH-FEM耦合法数值模拟

为了提高计算效率以及更好展现爆炸荷载下混凝土破坏过程，采用SPH-FEM耦合法对混凝土爆破成坑进行模拟。首先结合前人给出的C30混凝土Holmquist-Johnson-Cook（HJC）部分本构参数，通过理论推导等方法确定出剩余的参数；然后代入模型中计算，将数值解与实测数据进行对比；最后以峰值压力和峰值加速度作为考察对象，对HJC模型中21个参数敏感性进行分析。结果表明:SPH-FEM耦合法能直观地模拟爆炸荷载作用下爆坑的发展全过程，且能够较好地处理SPH边界问题；基于所给出的C30混凝土HJC本构参数，采用SPH-FEM耦合法对混凝土爆破破坏进行模拟，计算结果与实测数据吻合度高，表明HJC本构参数的确定具有合理性。此外，还发现HJC本构参数对爆破问题结果的敏感度各不相同，指出对峰值压力和峰值加速度均有较大影响的参数在确定的时候需引起足够的重视。

Numerical simulation of blasting damage in concrete using a coupled SPH-FEM algorithm

To improve the calculation efficiency and describe the failure process of concrete under blast loading, a coupled SPH-FEM algorithm was used to simulate blast crater of concrete in this study. First, based on the partial Holmquist-Johnson-Cook(HJC) constitutive parameters of C30 concrete, and the remaining parameters determined via theoretical derivation, the numerical calculation was performed and the results were then compared with the measured data by taking the parameters into the numerical model. The sensitivities of 21 parameters for the HJC model were finally analyzed with peak pressure and peak acceleration. The results show that the coupled SPH-FEM algorithm can simulate the whole process of blast crater under the blast loading, and it may accurately deal with the SPH boundary problem. Based on the parameters of C30 concrete HJC model, the calculated results of the coupled algorithm agree well with the experimental ones, which demonstrates the rationality of the determining method for HJC constitutive parameters. In addition, the parameters have different sensitivities to the results of blast problem, and these parameters significantly influencing the peak pressure and peak acceleration should be paid enough attention in the process of its determination.