无砂再生透水混凝土配合比设计

Design on Mix Proportion of No-fines Pervious Recycled Concrete

为研究无砂再生透水混凝土最优配合比．选择再生粗骨料粒径为5-10mm和10-20mm两种不同粒径．分别以骨料目标孔隙率（15％、20％、25％）和水灰比（0．35、0．4、0．45、0．5）为主要指标制作试件。采用CJJ／T135-2009《透水水泥混凝土路面技术规程》中的配合比计算方法进行配合比设计。通过对试块的抗压强度、抗折强度、透水系数、实测孔隙率的测定综合考虑透水混凝土各项指标，一个目标孔隙率可确定一个最优水灰比，从而获得最优配合比。研究表明，在骨料粒径为5-10mm、目标孔隙率15％时，水灰比为0．4；目标孔隙率20％时，水灰比为0．45的再生透水混凝土综合性能最好。在骨料粒径为10-20mm时，目标孔隙率25％、水灰比为O．4的再生透水混凝土综合性能最好。

To study the optimal mix proportion of no-fines pervious recycled concrete, the particle size of selected re- cycled coarse aggregate was 5-10mm and 10-20mm,the specimens were made from aggregate target porosity （15%, 20%, 25%） and water cement ratio （0.35, 0.4, 0.45, 0.5）. The mix proportion calculation was finished according to the method in CJJfF 135-2009 ＂Technical Specifications for Pervious Concrete Pavement＂. Through the measurement of compressive strength, flexural strength, permeability coefficient and measured porosity of specimens, and the comprehensive consideration of several kinds of indicator of pervious concrete, one target porosity can determine an optimal water cement ratio, finally the optimal mix proportion was obtained. The experimental results show that in the case of aggregate particle size of 5-10mm, the overall performance of recycled pervious concrete is the best when the target porosity is 15% and water ce- ment ratio is 0.4, and the target porosity is 20% and water cement ratio is 0.4. In the case of aggregate particle size of 10-20mm, recycled pervious concrete with target porosity of 20% and water cement ratio of 0.4 has the best overall performance.