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为研究掺入废砖块集料后水泥稳定碎石性能的变化规律,在试验中将废砖块集料按20%,40%,60%,80%和100%的比例(质量分数,后同)分别替代粗、细集料配制成2组集料后,用5%水泥拌和制备试件,并测试了混合料的击实特性和试件的抗压、抗折强度、抗压回弹模量、干缩以及抗冻性。结果表明:废砖块集料含量多的混合料最大干密度较小而最佳含水率较大;随着废砖块集料含量的增加,试件抗压强度、劈裂强度、抗压回弹模量、干缩应变和抗冻指数随之下降,而-15℃～40℃温缩应变随之增大;为满足规范对基层强度的最低要求,建议混合料中废砖块集料替代天然粗集料或细集料的替代率分别不要超过70%和90%;另外,在冬季严寒地区,还应该考虑废砖块集料的使用引起的强度损失。
In order to study the variation regularity of cement stabilized macadam after the aggregate was mixed into waste bricks, the aggregate of waste bricks was reduced by 20%, 40%, 60%, 80% and 100% (mass fraction, The same) were replaced coarse, fine aggregate prepared into two sets of aggregates, with 5% of cement prepared specimens, and tested the compaction compaction characteristics and specimens compressive, flexural strength, compression rebound Modulus, shrinkage and frost resistance. The results show that the maximum dry density of the mixture with more aggregate of waste bricks is smaller and the optimal moisture content is larger. With the increase of aggregate content of waste bricks, compressive strength, splitting strength, The modulus of elasticity, the shrinkage strain and the freeze-thaw index decrease, while the temperature-programmed strain increases from -15 ℃ to 40 ℃. In order to meet the minimum requirements of the standard for the strength of the grassroots, it is suggested that the waste brick aggregates in the mixture should be replaced The replacement rate of natural coarse aggregate or fine aggregate shall not exceed 70% and 90% respectively. In addition, in the cold winter area, the strength loss caused by the use of waste brick aggregates should also be considered.