掺加橡胶粉的水泥稳定碎石劈裂抗拉强度性能研究

Study on Splitting Tensile Strength of Cement Stabilized Macadam with Rubber Powder

随着我国经济高速发展,汽车日渐成为一种家用品,路面上的汽车越来越多,与之俱来的是大量废旧轮胎。如何合理利用这些废旧轮胎,俨然已经成为了当今社会急需解决的问题。环保型胶粉在公路施工中的应用对减少污染、保护自然资源和环境具有无可替代的现实意义。本课题主要研究掺加橡胶粉的水泥稳定碎石基层材料的劈裂抗拉强度。所做的主要工作和取得的成果如下:①原材料性能的分析:包括水泥、碎石和胶粉。采用胶砂试验测试水泥强度、凝结时间、筛分仪进行碎石筛分、测出碎石表观密度、吸水率以及压碎值。②进行击实试验,确定不同水泥剂量对应的最佳含水量及最大干密度。③进行7d无侧限抗压强度试验,确定合适的水泥剂量为4.8%,对应的最佳含水量为4.3%,最大干密度为2.305g/cm3。成型胶粉掺量不同的试件,进行劈裂抗拉试验,发现掺加胶粉不利于水泥稳定碎石力学性能,力学性能与胶粉掺量呈负相关,胶粉掺量越高,力学性能越差。

With the rapid development of China's economy,the automobile has become a kind of household goods,more and more cars on the road,with a lot of waste tires.How to make rational use of these waste tires has become an urgent problem in today's society.The application of environmental protection rubber powder in highway construction has irreplaceable practical significance for reducing pollution and protecting natural resources and environment.This paper mainly studies the splitting tensile strength of cement stabilized macadam base material mixed with rubber powder.The main work done and the results achieved are as follows:①Analysis of raw material properties:including cement,gravel and rubber powder.The cement-sand test was used to test the strength and setting time of cement,and the sieve was used to screen gravel,and the apparent density,water absorption and crushing value of gravel were measured.②The optimum moisture content and maximum dry density of different cement doses were determined by compaction test.③The 7d unconfined compressive strength test was conducted to determine the appropriate cement dose of 4.8%,the corresponding optimal moisture content of 4.3%,and the maximum dry density of 2.305g/cm3.Split and tensile tests were carried out on the samples with different dosage of molded rubber powder.It was found that the addition of rubber powder was not conducive to the mechanical properties of cement stabilized gravel.