不同工况对再生沥青混合料压实特性的影响

Influence of Different Working Conditions on Compaction Characteristics of Recycled Hot-mix Asphalt(RHMA)Mixture

为研究级配、沥青混合料回收料(reclaimed asphalt pavement,RAP)掺量、压实温度对再生沥青混合料压实特性指标空隙率、压实能量指数、压实速率、锁点的影响,设计正交试验,采用极差、方差分析因素与压实特性指标之间的影响程度,建立因素与压实特性指标之间的回归模型,分析了变化规律。在此基础上,采用实体工程进一步论证了不同因素对压实特性的影响。研究结果表明:级配、RAP掺量、压实温度均显著影响再生沥青混合料压实特性指标,级配的影响程度最高,RAP掺量影响程度相对较低;因素与压实特性指标空隙率、压实能量指数之间满足二次回归模型,且空隙率、压实能量指数与级配、RAP掺量、压实温度的变化呈负相关;以福银高速三明段养护工程为例,进一步论证了级配对再生沥青混合料空隙率的影响,发现越细的级配越容易压实。

In order to investigate the influence of gradation,reclaimed asphalt pavement(RAP)content and compaction temperature on the compaction characteristics of recycled hot-mix asphalt(RHMA)mixture,such as void ratio(VV),compaction energy index(CEI),slope of accumulated compaction energy(K)and lock point(LP),the orthogonal experiment was designed,and the influence degree between the factors and the compaction characteristic index were analyzed by range and variance analysis,and variation law was analyzed by regression model.In addition,the influence of different factors on compaction characteristics was further demonstrated by field construction.The results show that gradation,RAP content and compaction temperature have significant influence on the compaction characteristics of RHMA,and the influence degree of gradation is higher than that of RAP content.The relationship between the factors and the compaction characteristic indexes of VV and CEI were established by quadratic regression model,and the VV and CEI are negatively correlated with the changes of gradation,RAP content and compaction temperature.The proposed results were proved valid in the project of the Sanming section of Fuzhou-Yinchuan expressway,and the gradation can significantly affect the VV of recycled asphalt mixture,and the finer the gradation,the easier the compaction.