建筑垃圾用作路基填料的物理力学性质分析

Analysis of physical and mechanical properties of construction waste used as roadbed filling

通过以某建筑垃圾处理厂再生料为研究对象,结合《公路土工试验规范》(JTG E40-2007)中的标准试验方法,对建筑垃圾再生料填的骨料组成、天然含水率、原始级配是否良好、击实之后级配变化、不同砖混凝土配比对含水率及最大干密度的影响等方面进行了研究。试验结果显示:由筛分试验得到建筑垃圾再生材料的初始骨料级配不良,按三层法将再生料分三次装入击实筒内击实后,按照加入击实筒的顺序分别第一、二、三层进行筛分,得到第一、二、三层均达到规范要求,且级配良好,可以满足路基填料的使用要求;根据取样现场实际情况设计的五种试验配比分别为5:5、6:4、7:3、8:2、9:1,随着混合料中砖渣含量的增加及混凝土渣含量的减少,各混合比例试样的最佳含水率逐渐增大,与之相应的最大干密度却随之减小,砖渣与混凝土渣混合比例5:5时的最佳含水率最小,最大干密度最大。

In this paper,the recycled material of a construction waste treatment plant is taken as the research object,combined with the standard test method in“Code for Highway Geotechnical Test”(JTG E40-2007),the aggregate composition,natural moisture content,good original gradation,gradation changes after compaction,and the influence of different proportions of brick concrete on moisture content and maximum dry density of construction waste recycled material were studied.The test results show that:according to the screening test,the original aggregate grading of the construction waste recycling material is not good.According to the three-layer method,the recycled materials are divided into three times into the compacting cylinder.After compacting,the first,second and third layers are screened according to the order of adding the compacting cylinder,and the grading is good,which can meet the requirements of sub-grade filling.According to the actual situation of the sampling site,the ratios of five kinds of tests designed are 5:5,6:4,7:3,8:2 and 9:1 respectively.With the increase of the content of brick slag in the mixture and the decrease of the content of concrete slag,the optimal moisture content of the samples in each mixing ratio increases gradually,while the corresponding maximum dry density decreases accordingly.When the mixing ratio of brick slag and concrete slag is 5:5,the optimum water content is the minimum and the maximum dry density is the maximum.