冲击压缩载荷下大尺寸混凝土力学响应的数值模拟

利用Ansys/Ls-dyna有限元软件模拟打击气压为0.6、0.8、1.2MPa下大尺寸混凝土的SHPB束杆试验. 试验结果表明, 模拟得到的冲击试验过程中束杆传播的入射、反射及透射应力波信号与实测结果比较, 波形总体吻合较好, 入射波偏差很小, 反射波和透射波差异略大; 打击气压越大, 试样破损速度越快. 数值模拟给出了不同打击气压下大尺寸混凝土破坏形貌变化的规律.

. Numerical simulation on mechanical response of concrete subjected to impact compressive loading

The numerical simulations of the bundled Hopkinson pressure bar tests of large-size concrete with 0.6, 0.8 and 1.2 MPa fire pressures are studied using the finite element software of Ansys/Ls-dyna in this paper. The incident stress waves, reflected stress waves and transmitted stress waves are obtained in the bundled bars of experiments and simulations during the process of impact, and the error analysis is consequently made. The results show that the waves of simulation are in good agreement with the experimental data. The deviation of incident stress waves is small enough. This study provides the explanation for the trivial difference of the reflected stress waves and the transmitted stress waves. The conclusion from this study is that the larger the blow air pressure, the faster the damage speed. The trends are also analyzed of the damage appearance changes of large-size concrete subjected to different fire pressures