一种高粘弹改性沥青及其混合料性能与工程应用

A High Viscoelastic Modified Asphalt and Its Mixture Performance and Engineering Application

采用SBS、高粘弹改性剂制备一种复合高粘弹改性沥青,通过针入度、软化点、延度、60℃动力粘度、135℃旋转粘度、弹性恢复等参数试验,评价其沥青的常规性能与粘弹性能,确定了高粘弹改性剂的最佳掺量。基于此,评价其混合料的高温性能、水稳定性、低温抗裂性及疲劳性能。结果表明,与SBS改性沥青相比,SR-1高弹剂的掺量为8%时,5℃延度提高48 cm、60℃动力粘度大于3×10^(5) Pa·s、剪断30 s时其弹性恢复速率提高7.3%/min;与SBS改性沥青混合料相比,高粘弹改性沥青混合料的高温稳定性提高了11.4%、低温抗裂性提高了60.9%、水稳定提高了8.6%、疲劳性能提高了175%。试验段铺筑验证表明,高粘弹改性沥青混合料更能适应较低温环境下的施工,且其各项性能均满足现行规范要求。

SBS and high viscoelastic modifier were used to prepare a composite high viscoelastic modified asphalt.Through the tests of penetration,softening point,ductility,60℃dynamic viscosity,135℃rotational viscosity and elastic recovery,the conventional and viscoelastic properties of the asphalt were evaluated,and the optimum content of high viscoelastic modifier was determined.On the basis,the high temperature performance,water stability,low temperature crack resistance and fatigue performance of the mixture are further evaluated.The results show that compared with SBS modified asphalt,when the content of SR-1 high elastic agent is 8%,the ductility at 5℃is increased by 48 cm,the dynamic viscosity at 60℃is more than 3×105 Pa·s,and the elastic recovery rate is increased by 7.3%/min when cut for 30 s.Compared with SBS modified asphalt mixture,high viscoelastic modified asphalt mixture improves high temperature stability by 11.4%,low temperature crack resistance by 60.9%,water stability by 8.6%and fatigue performance by 175%.Through the paving verification of the test section,the high viscoelastic modified asphalt mixture can better adapt to the construction under low temperature environment,and its properties meet the requirements of the current specifications.