C45珊瑚混凝土的冲击压缩性能试验及数值模拟

Experiment and numerical simulation on impact compressive properties of C45 coral aggregate concrete

为了研究珊瑚混凝土(CAC)的动态力学性能,采用试验研究和数值模拟相结合的方法对强度等级为C45的CAC冲击压缩性能及破坏特征进行了分析.首先,通过实验得到了CAC的压缩强度、应力应变曲线和破坏特征;然后,采用HJC模型对其冲击实验进行数值模拟,并将模拟结果与试验结果进行对比,分析HJC模型及其参数的可靠性.结果表明:冲击压缩荷载作用下的CAC呈典型脆性破坏形态,其抗压强度具有明显的应变率效应;可以采用欧洲混凝土委员会推荐的计算模型来分析预测CAC的动态增强因子;动态屈服强度试验值与模拟值的误差(1.76%~7.71%)在允许范围内,说明HJC模型及其模型参数在C45 CAC的冲击力学性能分析方面具有较高的可靠性.

To investigate the dynamic properties of coral aggregate concrete(CAC),the impact compressive properties and the failure patterns of C45 CAC were analyzed by combining experiments with numerical simulation.Firstly,the compressive strength,the stress-strain curve and the failure pattern of C45 CAC were tested.Then,the Holmquist-Johnson-Concrete(HJC)model was used to simulate the impact tests,and the reliability of the HJC model and the model parameters was evaluated by the comparison of the simulation and the experimental results.The results indicate that CAC under impact loading exhibits the typical brittle failure,and the compressive strength of CAC has the obvious strain-rate effect.The dynamic increase factor of CAC can be predicted by using the calculation model proposed by the European Committee for Concrete.The errors between the simulation results and the experimental ones(1.76%to 7.71%)are in the error range,improving the high rationality of the HJC model and the model parameters on the properties analysis of C45 CAC under impact loading.