Experimental Study on the Performance of Sand-construction Waste Recycled Mixtures for Subgrade Backfill
The composition,gradation and physical and mechanical properties of five kinds of construc-tion waste mixtures and sand were tested by indoor tests,and the crushing law of construction waste mixtures in subgrade application scenarios was analyzed.A design method for optimizing the mixture ratio of sand and construction waste was established,and the effects of sand content(0％,20％,40％,60％and 80％by mass)on the maximum dry density,optimum moisture content,compaction and bearing capacity of recycled mixture were studied.The results show that the nominal maximum particle size and gradation of aggregate have significant influence on the performance of construction waste mixture filling subgrade.Among the five kinds of graded construction waste mixtures,the rela-tive crushing rate and crushing index of aggregates of Class Ⅰ and Class Ⅱ mixtures are small,and the bearing capacity of Class Ⅰ mixture is the best.Adding sand can change the gradation structure of con-struction waste mixture.With the increase of sand content,the optimum water content of construc-tion waste mixture decreases,and the maximum dry density and CBR value increase first and then de-crease.According to the quadratic function prediction model of CBR value,it can be known that the bearing capacity of mixture filling subgrade is the best when the sand content is 45％.
roadbed engineeringconstruction waste recycled mixturesandy soilroad performanceCBR valuemaximum dry density
万方数据
维普
