RAP掺量对热再生沥青混合料性能影响分析

为了确定热再生沥青混合料合理的旧沥青路面材料(RAP)掺量,依托浙江省102省道杭昱线(临安段)旧沥青路面厂拌热再生利用试验路,通过大量室内试验,进行了不同RAP掺量的热再生沥青混合料AC-20C的目标配合比设计和路用性能分析.研究结果表明,旧沥青中掺加5%的再生剂和70%的新沥青,再生后的调和沥青可以达到A-70#目标沥青的性能要求;随着RAP掺量的增加,热再生沥青混合料的总最佳油石比和新料最佳油石比线性增加,而新沥青用量线性减少;RAP掺量在20%~40%之间时,热再生沥青混合料的各项路用性能均满足规范的技术要求,且随着RAP掺量的增加,热再生混合料的高温稳定性呈指数关系增强,低温抗裂性、抗渗性和抗滑性呈线性减弱,水稳定性在RAP掺量为30%时达到最大.为此,按30%RAP掺量铺筑了试验路,经通车两年考验,取得了优良的应用效果.

Influence analysis of RAP contents on performances of hot recycled asphalt mixture

In order to determine a reasonable content of reclaimed asphalt pavement （RAP）materials for hot recycled asphalt mixtures,relying on the test road of hot mix plant recycling of existing asphalt pavement in Hang-Yu Line （Lin＇an Section） of 102 Provincial Highway in Zhejiang Province,and through a large number of laboratory tests,the design of target mix proportions and the analysis of pavement performances for hot recycled asphalt mixture AC-20C with different RAP contents have been carried out.The results show the old asphalt mixed with 5％ of regenerant and 70％ of new asphalt,and the blended asphalt after regeneration can be achieved the performance requirements of A-70 # of target asphalt.With the increase of RAP content,the total optimal asphalt-aggregate ratios and the optimal asphalt-aggregate ratios of new mixture in hot recycled asphalt mixture increase linearly,but the new asphalt contents decrease linearly.When the RAP contents are between 20％～40％,all the pavement performances of hot recycled asphalt mixture can satisfy the technical requirements of specifications.In addition,with the increase of RAP contents,the high temperature stability of hot recycled asphalt mixture enhances exponentially,the low temperature crack resistance,the impermeability and the anti-slip performance decrease linearly,and the water stability reaches the maximum in 30％ of RAP content.Therefore,the test road has been paved in accordance with 30％ of RAP content,and the good application effect has been achieved after 2 years of open traffic.