【摘要】 采用改进的分离式Hopkinson压杆装置,结合应变直测技术,分别对常温以及经历400℃和800℃高温的钢纤维活性粉末混凝土(SFRPC)进行了单轴冲击压缩试验,减少了传统的Hopkinson压杆试验中的入射波的高频震荡,使得应变率的波动性明显减小。试验结果表明,经历400℃和800℃后,钢纤维活性粉末混凝土的峰值应力分别将为常温状态的62%和27%,弹性模量降为83%和35.6%,同时,高温也改变了试件的破坏形态。对活性粉末混凝土冲击过程中的能量吸收性能进行分析,试件在经历高温后,能量吸收能力大幅度下降,400℃和800℃的能量吸收能力分别是常温下的67.4%和42.6%。更多还原

【Abstract】 Combined with direct strain gauge measurement method,the modified split Hopkinson pressure bar was adopted to investigate the behavior of steel fiber reactive powder concrete exposed to 400 ℃ and 800 ℃ under axial compressive loading.This method decreased the high frequency fluctuation of input shaky stress pulse in traditional SHPB test.The experimental results showed that compared with normal temperature,the compressive strength of SFRPC exposed to 400 ℃ and 800 ℃ decreased to 62% and 27%,and the elasticity modulus decreased to 83% and 35.6%,respectively.At the same time,the failure forms of the specimens were changed also.The energy absorbing capability during the impact process was analyzed,and it was found that the energy absorbing capability of SFRPC deteriorated greatly after exposed to high temperature.更多还原