聚丙烯纤维水泥稳定碎石抗裂性能研究

为了研究聚丙烯纤维水泥稳定碎石的抗裂性能,对聚丙烯纤维水泥稳定碎石和普通水泥稳定碎石梁式试件进行了干缩试验、温缩试验和抗弯拉试验,采用干缩能抗裂系数和温缩能抗裂系数作为抗裂性的评价指标,对材料的抗裂性能随养护龄期、纤维掺量以及水泥掺量变化的规律进行了分析.结果表明,聚丙烯纤维的掺入可显著地增强水泥稳定碎石的抗干缩开裂性能和抗温缩开裂性能;随养护龄期的增长,聚丙烯纤维水泥稳定碎石的抗干缩开裂性能逐渐增强,而抗温缩开裂性能有略微的减小;在纤维体积分数小于0.1%的范围内,随着纤维体积分数的增加,水泥稳定碎石的抗干缩、抗温缩开裂性能均逐渐增强;随水泥掺量的增加,聚丙烯纤维水泥稳定碎石的抗干缩、抗温缩开裂性能均有逐渐减小的趋势.

Research on Crack Resistance of Cement Stabilized Macadam Reinforced with Polypropylene Fiber

To investigate the crack resistance of cement stabilized macadam,the experiments of dry shrinkage,thermal shrinkage,flexural strength and flexural elastic modulus of polypropylene fiber reinforced cement stabilized macadam and common cement stabilized macadam were conducted.Adopting dry shrinkage energy anti-cracking coefficient and thermal shrinkage energy anti-cracking coefficient as evaluation index of crack resistance,the effects of curing period,fiber content and cement content on the crack resistance were investigated.The results indicate that the addition of polypropylene fiber can enhance dry shrinkage crack resistance and thermal shrinkage crack resistance.With increase of curing period,dry shrinkage crack resistance increases gradually,while thermal shrinkage crack resistance decreases slightly.When the fiber content does not exceed 0.1%(by volume),dry and thermal shrinkage crack resistances are enhanced with increase of polypropylene fiber content.With increase of cement content,dry and thermal shrinkage crack resistances both tend to reduce.