水灰比及再生骨料代替率对再生混凝土抗压强度的影响研究

The Influence of Water Cement Ratio and Replacement Ratio of Recycled Aggregate on Compressed Strength of Recycled Concrete

为研究水灰比及再生骨料代替率对再生混凝土抗压强度的影响,以实验室废弃C30混凝土试块为原材料制备C30再生粗骨料混凝土,设计3种水灰比(0.43,0.53,0.63)和4种再生骨料替代率(0,25%,50%,75%)配置再生混凝土,制作了36个试块,研究了再生粗骨料不同代替率、水灰比对再生混凝土28d抗压强度的影响,试验表明,混凝土强度随水灰比增大而减小;当水灰比相同时,混凝土的抗压强度随再生骨料代替率提高,先增大后减小,再生骨料代替率为50%,混凝土的强度达到最大。

In order to study the influence of water cement ratio and recycled aggregate substitution rate on the compressive strength of recycled concrete,the recycled coarse aggregate concrete C30 was prepared with the waste C30 concrete test block as the raw material.Three kinds of water cement ratios(0.43,0.53,0.63)and four kinds of recycled aggregate substitution rates(0,25%,50%,75%)were designed,and recycled concrete were prepared,36 test blocks were made to study the influence of different replacement rates of recycled coarse aggregate and water-cement ratio on compressive strength of recycled concrete at 28d.The test results show that the strength of concrete decreases with the increase of water cement ratio,when the water-cement ratio is the same,the compressive strength of concrete increases with the replacement rate of recycled aggregate,which first increases and then decreases.The replacement rate of recycled aggregate is 50%,and the strength of concrete reaches the maximum.