高温后钢管活性粉末混凝土的动态力学性能

Mechanical properties of reactive powder concrete-filled steel tube after exposure to high temperature under impact loading

采用霍普金森压杆装置对高温后钢管活性粉末混凝土(reactive powder concrete-filled steel tube,RPC-FST)进行冲击压缩实验,分析了应变率效应及温度效应对试件动态力学性能的影响。结果表明:高温(200、300℃)后RPC-FST仍具有较好的抗冲击能力、延性和完整性;冲击荷载作用下,RPC-FST的应变率效应明显弱于RPC的应变率效应;随着过火温度的提高,RPC-FST的峰值应力逐渐增大,变形能力增强,抗冲击能力提高。动力提高系数随过火温度的提高而增大,说明高温后RPC-FST的应变率效应更显著。

Experiments on reactive powder concrete-filled steel tube （RPC-FST） specimens after expo- sure to high temperature were performed by using a split Hopkinson pressure bar （SHPB） apparatus, and the influences of strain rate effects and temperature effects on the dynamic behaviors of RPC-FST were investigated. Test results show that the RPC-FST specimens after exposure to high temperature have excellent impact-resistance, ductility and integrity. The strain rate effects of the RPC-FST speci- mens are weaker than those of the RPC specimens under impact loading. The peak stress of the RPC- FST specimens increases as the temperature increases, and the deformation capability and impact-re- sistance increase. The dynamic increase factor （DIF） increases as the temperature increases. It means that the strain rate effects of RPC-FST become more obvious after exposure to high temperature.