动态劈裂实验的数值模拟及讨论

利用分离式霍普金森压杆(SHPB)可以进行混凝土类材料高应变率下的劈裂实验,目前公认的方法是通过透射波信号得到劈裂强度和相应的平均应变率.文章通过数值模拟对这种方法的有效性进行了讨论,发现在高应变率下,混凝土劈裂不满足中心开裂条件.因此上述基于弹性静力学平面问题的传统处理方法会产生一定的误差.文章还分析了不同试样尺寸对动态劈裂实验精度的影响.

Numerical simulation and discussion of the dynamic splitting test

An experiment method of using the split Hopkinson pressure bar(SHPB) is proposed to perform dynamic split testing of brittle materials like concrete at a high strain rate,and the currently accepted method for the experiment is to obtain the tensile strength and the average strain rate by the transmitting wave signals.The paper discusses the effectiveness of this method through numerical simulation and it is found that concrete splitting is not in accordance with the conditions of center split at the high strain rate.So the traditional approach based on the elastostatic plane theory may bring some errors.The paper also analyzes the influences of different sepcimen size on the accuracy of the dynamic split testing.