钢纤维对再生混凝土抗冲击性能的影响

Impact Resistance of Recycled Aggregate Concrete Reinforced with Steel Fibers

为研究不同再生骨料取代率、钢纤维掺量和纤维类型对再生混凝土(RAC)抗冲击性能的影响,采用自由落锤冲击试验装置,对其进行抗冲击试验。利用两参数Weibull分布函数模型对试件抗冲击初裂次数和破坏冲击次数的概率分布规律,进行了拟合检验和失效概率预测分析;并以抗冲击延性比、抗裂性能定量评价了钢纤维再生混凝土(SFRAC)的抗冲击性能。研究结果表明:RAC的抗冲击性能随再生骨料取代率的增加逐渐降低;随着钢纤维掺量的增多,不同再生骨料取代率RAC的抗冲击性能均有不同程度地提高;SFRAC试件抗冲击次数的分布特征能很好地服从于Weibull分布;端钩形钢纤维对RAC抗裂性能的改善效果较波纹形钢纤维的更为显著。

In order to investigate the recycled aggregate replacement ratio,the contents and types of steel fibers on the impact resistance of recycled aggregate concrete(RAC),the drop-weight impact tests were carried out on different kinds of RAC specimens.A two-parameter weibull distribution was adopted to describe the number of blows for initial crack and final failure well as the failure probability.Moreover,the impact resistance of steel fiber reinforced RAC(SFRAC)was evaluated by ductility ratio and crack resistance.The experimental results show that the impact resistance of RAC decreases with the increase of recycled aggregate replacement ratio but increases with the steel fiber content.In addition,the weibull distribution was able to describe the impact resistance of SFRAC.And end hook steel fibers have better crack resistance capacity compared with that of corrugated steel fibers.