Using recycled brick powder to partially replace cement to prepare concrete is one of the ways to realize the recycling of construction waste.The activated brick powder was used as an auxiliary cementing material to replace part of the cement to prepare UHPC.The law and mechanism of autogenous shrinkage and drying shrinkage of recycled brick powder UHPC under different substitution rates were studied and analyzed.Based on the experiments,a prediction model for the autogenous shrinkage and drying shrinkage of recycled UHPC was established.The results show that replacing cement with recycled brick powder can reduce the autogenous shrinkage of UHPC,and the autogenous shrinkage rate of UHPC decreases with the increase of the replacement rate of brick powder.The drying shrinkage of UHPC can be reduced by replacing cement with recycled brick powder,and the drying shrinkage of UHPC decreases first and then increases with the increase of the replacement rate of brick powder.When the brick powder replacement rate is 30%,the drying shrinkage of UHPC is the smallest,which is 49.7%lower than that of the baseline group.The autogenous shrinkage rate and drying shrinkage rate prediction models are in good agreement with the test results,and can be used to predict the shrinkage development of recycled brick powder UHPC.
关键词
再生砖粉/UHPC/自收缩/干燥收缩/收缩率预测模型
Key words
recycled brick powder/UHPC/autogenous shrinkage/drying shrinkage/shrinkage rate prediction model
维普
万方数据