掺聚丙烯颗粒混凝土抗冻性能试验研究

Experimental study on freezing resistance of recycled polypropylene fine aggregate concrete

表面粗糙再生聚丙烯颗粒等体积代替细骨料0、4%、6%、8%,制作不同配合比的混凝土试件,试验选择慢冻法和快冻法,研究冻融0、30、60、90、120、150次再生聚丙烯混凝土试件质量、抗压强度、抗折强度和动弹性模量变化规律和损伤情况,并分析抗冻性。结果表明:增加冻融次数,不同掺量的再生聚丙烯混凝土试件质量、抗压强度、抗折强度、相对动弹性模量均不断降低,损伤增大。适量掺加表面粗糙再生聚丙烯颗粒,可提升强度和动弹性模量,并有效抑制质量损失、强度劣化,提升抗冻性能。综合考虑混凝土抗冻性能,建议掺入表面粗糙的再生聚丙烯颗粒的最佳体积掺量为6%。

The different proportions of concrete specimens is made with the surface roughened recycled polypropylene granules that replaced with the equal volume fine aggregate 0,4%,6% and 8%.The experiment selected slow freezing method and quick freezing method.The mass compressive strength flexural strength and dynamic elastic modulus of recycled polypropylene concrete specimens with0,30,60,90,120 and 150 times freezing-thawing and analyze the frost resistance.The results show that with the increase of freeze-thaw times.the mass compressive strength flexural strength and relative dynamic elastic modulus of recycled polypropylene concrete with different concrete of recycled polypropylene decrease continuously and the damage is increased.Appropriate amount of surface roughened recycled polypropylene particles can improve the strength and dynamic elastic modulus and effectively inhibit the quality loss strength degradation and improve the anti freeze performance.Considering the frost resistance of concrete the optimum volume of recycled polypropylene.Particle with rough blended info the surface is 6%.