C30混凝土冲击绝热关系和Grneisen型状态方程的实验研究

Experimental study on the shock Hugoniot relationship and the Grneisen-type equation of state for C30 concrete

采用一级气炮加载技术和锰铜压力计测试技术,对含初始空隙的C30混凝土在一维应变条件下的冲击特性进行了实验测量和分析.基于锰铜压力计测量的压力波形,确定了C30混凝土材料的冲击绝热关系,即冲击波速度D与波后粒子速度u之间满足线性关系.再从C30混凝土的冲击绝热数据出发,获得了计及初始空隙度Ф0影响的多项式形式Grneisen型状态方程中的各项系数.实测压力波形还显示:不同位置处的压力波形在迅速上升至峰值后均随时间逐渐衰减,而冲击波峰值又随传播距离而衰减,从而表明C30混凝土材料的率相关特性不能忽略,呈现出明显的应力松弛特征和耗散特征.

The shock properties of C30 concrete with initial porosity is investigated by gas gun planar impact technique. The manganin pressure gauge is used to measure the pressure-time curves of the samples. It is shown by the experimental studies on the shock Hugoniot relationship and the Grǖneisen-type equation of state for C30 concrete that the D-u shock Hugoniot relationship is described by the linear relation, and the material parameters in the Grfineisen-type equation of state are determined. Moreover, it is observed from the measured pressure-time curves that the rate-sensitivity of dynamic response for C30 concrete is not negligible, showing marked stress relaxation and dissipation.