早强型冷再生乳化沥青设计及性能

Design and Performance of Early Strength Cold-recycled Emulsified Asphalt

根据乳化沥青冷再生混合料施工不同阶段对乳化沥青的性能要求,提出了乳化沥青冷再生混合料强度随着时间变化的理想曲线,确定了早强型冷再生乳化沥青的开发思路。通过降低木质素型乳化剂用量,优选非离子乳化剂进行复配,形成了4种乳化沥青配方。通过拌和试验和旋转压实试验对冷再生混合料的和易性进行评价,通过黏聚力试验和扫刷试验对冷再生混合料的早强性进行评价。通过路用性能试验,进一步验证了两种早强型乳化沥青冷再生混合料的性能。结果表明:E-1乳化沥青冷再生混合料保水性差,黏聚力低,E-3乳化沥青冷再生混合料裹覆性差,黏聚力低,E-1和E-3乳化沥青不满足早强型冷再生乳化沥青的要求;E-2和E-4乳化沥青具有良好的施工和易性和早强性能,并且基本性能都满足规范要求;E-2乳化沥青冷再生混合料的劈裂强度、干湿劈裂强度比、马歇尔稳定度、水稳定性指标和动稳定度都优于进口产品,E-4乳化沥青冷再生混合料的各项性能指标都能满足规范技术要求;综合乳化沥青的施工和易性,早强性以及冷再生混合料的路用性能来看,E-2乳化沥青和E-4乳化沥青可以作为早强型冷再生乳化沥青,其中E-2乳化沥青性能最佳。

The ideal curve of strength change with time of cold-recycled emulsified asphalt mixture is presented according to its performance requirement at different construction stage and the development idea of the early strength cold-recycled emulsified asphalt is proposed.Four emulsified asphalt formulas are established by reducing the amount of lignin emulsifier and introducing the non-ionic emulsifier.The construction work-ability of the cold-recycled emulsified asphalt mixtures is evaluated by the mixing test and rotary compaction test.The early strength performance is evaluated by the cohesion test and brush test.The road performances of 2 early strength cold-recycled emulsified asphalt mixtures are further studied by the lab tests.The result shows that(1)E-1 and E-3 emulsified asphalt cannot meet the requirements of early strength cold-recycled emulsified asphalt due to the poor water retention and low cohesion;(2)the construction work-ability and early strength performance of the E-2 and E-4 emulsified asphalt are good and their basic performances meet the specification requirements;(3)the splitting strength,wet and dry splitting strength ratio,Marshall stability,water stability indicators and dynamic stability of the E-2 emulsified asphalt mixture are all better that those of the imported product while the road performance indicators of the E-4 emulsified asphalt mixture all meet the specification requirements;(4)the E-2 emulsified asphalt and E-4 emulsified asphalt can both used as the cold-recycled emulsified asphalt while the E-2 emulsified asphalt has the best performance.