钢纤维再生混凝土的抗折强度试验研究

对含0%、30%、50%、70%及100%再生粗集料(RCA)的钢纤维再生混凝土(SRC)的抗折强度进行了较为系统的研究。首先在室内对RCA的密度、洛杉矶磨耗和压碎指标等基本性能进行了测试,然后针对不同配合比的SRC试件,在室内进行了抗折强度等试验。结果表明,RCA的含量和水灰比等因素对SRC的抗折强度有较大的影响,在设计抗折强度为6.0MPa,钢纤维的掺量在1.0%的条件下,当RCA的含量小于50%,水灰比在0.44~0.47时,SRC的28d抗折强度比较接近于基准钢纤维混凝土,而超出此范围时,SRC的抗折强度会明显降低。最后,通过工程应用对含30%RCA的SRC的相关性能进行了检测,结果证明,适当配合比的SRC能够满足I级刚性路面的抗折强度要求。

INVESTIGATION ON THE TEST OF FLEXURAL STRENGTH OF STEEL FIBER RECYCLED CONCRETE

The flexural strength of steel fiber recycled concrete (SRC) with different recycled coarse aggregate(RCA) replacement ratio and different water/cement(W/C) ratios was investigated,these SRC were mixed with RCA in weight percentage of(referred to total coarse aggregate) 0%,30%,50%,70% and 100%. Firstly,the basic performances of RCA were undertaken in the interior tests,mainly including the density,Los Angeles abrasion loss and crush index,etc.,and then the flexural strength of SRC has also been undertaken.The results indicated that the flexural strength of SRC can be greatly influenced by the content of RCA and different(W/C) ratios.On condition that the design flexural strength was 6.0 MPa and the content of steel fiber was 1.0%,when the content of RCA is less than 50% and W/C ratios is from 0.44 to 0.47,the 28d flexural strength of SRC is very approaching to the plain steel fiber concrete.However,if the data were not in these ranges,the flexural strength of SRC would have a remarkable decrease.Finally,the SRC content with 30% RCA has been applied in a trial pavement section,the data of flexural strength from in-situ could have met the demand of grade I.