高温后大理岩动态劈裂拉伸试验研究

为了研究高温处理后的岩石材料在冲击加载速率作用下的动态劈裂拉伸性能，利用大直径分离式霍普金森压杆试验设备对经历不同高温作用冷却后的“大理岩”平台巴西圆盘试样进行不同加载速率作用下的径向冲击试验。研究了高温后大理岩的动态劈裂拉伸强度及动态劈裂破坏形式随温度和冲击加载速率的变化规律。试验结果表明，与静态劈裂拉伸强度相比，经历不同高温作用冷却后，大理岩的动态劈裂拉伸强度有明显的提高，表现出显著的冲击加载速率强化效应，同一冲击加载速率作用下，随着温度的升高，动态劈裂拉伸强度表现出先增大后减小的变化趋势；高温后大理岩的动态劈裂破坏形式受到冲击加载速率和温度的共同影响。

Experimental study of dynamic tensile behaviors of marble after high temperature

In order to investigate the dynamic tensile strength of rock after high temperature under impact loading, the dynamic flattened Brazilian disc experiments of marble after different temperatures subjected to radial impact compression are carried out by using split Hopkinson pressure bar (SHPB). The temperature and impact loading rate effects on the dynamic tensile strength and dynamic tensile failure form of marble under impact loading after high temperatures are analyzed. It is demonstrated that after different high temperatures the dynamic tensile strength of marble is substantially higher than the static tensile strength and has an obvious impact loading rate strengthening effect. As temperature increases, the dynamic tensile strength of marble under the same impact loading rate increases first and then decreases. Meanwhile, the temperature and impact loading rate both have strong influence on the dynamic tensile failure form of marble under impact loading after high temperature.