厂拌热再生沥青混合料的最佳RAP掺量研究

Investigation of Optimum RAP Contents in Hot Recycled Asphalt Mixture

将回收沥青路面材料(RAP)进行分为两档,并分别检测各档中沥青含量与矿料级配,通过马歇尔试验确定了厂拌热再生沥青混合料AC-13与AC-20在RAP掺量为10%,20%,30%,40%,50%条件下的最佳沥青用量及配合比。在最佳沥青用量的条件下,分析RAP掺量变化对再生沥青混合料高温性能、低温性能和水稳定性能进行研究,最后通过修筑试验路对厂拌热再生沥青混合料的路用性能进行验证。结果表明:再生沥青混合料的低温性能和水稳定性能随着RAP掺量的增加呈现先提高后下降的趋势,在30%RAP掺量时达到峰值;高温性能随着RAP掺量的增加而提高,综合各项性能推荐采用30%作为RAP掺量。

The reclaimed asphalt pavement（RAP） material was classified into two categories and the gradation and asphalt content of RAP were examined for each category. The Marshall design method was adopted to obtain the optimum asphalt content and mixture ratio in the hot recycled asphalt mixture AC-13 and AC-20 under the conditions of 10%, 20%, 30%, 40% and 50% content of RAP respectively. Effects of RAP changes on the high temperature stability, low temperature performance and water stability of reclaimed asphalt mixture with the optimum asphalt content were evaluated. Finally, the test road was constructed to verify the road performance of hot recycled asphalt mixture. Research results show that the low temperature performance and water stability of hot recycled asphalt mixture increased first and then decreased along with the increase of content of RAP, and the optimum RAP content was 30%. The high temperature stability of hot recycled asphalt mixture improved with the increase of RAP content. With comprehensive consideration of the properties of hot recycled asphalt mixture,30% content of RAP was recommended.