聚丙烯纤维长径比对再生透水混凝土改性研究

Study on the influence of polypropylene fiber length ratio on recycled permeable concrete

研究聚丙烯纤维长径比对再生透水混凝土的性能影响,选用直径分别为31、450μm的2种纤维,采用28 d抗压强度、劈裂抗拉强度、连续孔隙率、透水系数以及耐磨性能试验评价长径比对再生透水混凝土性能影响。结果表明:再生集料对透水混凝土28 d抗压强度有增强作用,但其他性能均小于新集料混凝土;2种纤维长径比对再生透水混凝土28 d抗压强度、透水性能存在较大甚至相反的影响规律,对劈裂抗拉强度与耐磨性能存在相似的影响规律,均为先提升,后降低。除透水性能外,聚丙烯细纤维与粗纤维最佳长径比分别为378、100时,对应长度分别为12、45 mm。

In order to study the impact of polypropylene fiber length ratio on the performance of recycled permeable concrete,31 m and 450 m diameter fibers are selected to evaluate the effect of reclaimed permeable concrete with 28d compressive strength,split tensile strength,continuous porosity,permeability coefficient and wear resistance test.The test shows that the recycled aggregate enhances the compressive strength of 28 d permeable concrete,but other properties are less than the new aggregate concrete;the length ratio of the two fibers and permeability performance of 28 d,which have similar effects on the split tensile strength and wear resistance are improved first and then reduced.The results show that,except for the water permeability performance,the optimal aspect ratio of polypropylene fine fiber to crude fiber is 378 and 100,with the corresponding lengths of 12 mm and 45 mm,respectively.