基于不停航施工的沥青混合料仓储老化性能研究

Study on finished product storage aging performance of asphalt mixture based on non-suspend air construction

为研究不停航施工期间拌合温度与成品仓储存时间对沥青混合料老化性能的影响,分别对不同拌合温度(170、180、190℃)和储存时间(0、4、8、12 h)的AC-20沥青混合料开展车辙试验、小梁低温弯曲试验、水稳定性试验和疲劳试验以分析其老化性能。结果表明:随着拌合温度升高或储存时间延长,沥青混合料仓储老化程度逐渐增大,老化后的沥青混合料动稳定度增大,最大弯拉应变、残留稳定度、冻融劈裂残留强度比(TSR,tensile strength ratio)、疲劳寿命(180℃)减小,且老化对沥青混合料的TSR影响最大;综合考虑沥青混合料现场施工温度与其老化性能,建议AC-20沥青混合料的最佳拌合温度为180℃,储存时间不宜超过6.7 h。

In order to study the influence of asphalt mixture temperature and finished product storage time on the aging performance of asphalt mixture in non-suspend air construction,this thesis analyzes the aging performance of AC-20 asphalt mixture under different temperatures(170℃,180℃,190℃)and different time lengths of the finished product storage(0 h,4 h,8 h,12 h)through the high temperature rutting test,low-temperature trabecular bending test,water stability test and fatigue test.The results show that with the increase of mixing temperature or storage time,the finished product storage aging degree of mixture gradually increases;the dynamic stability of the aging asphalt mixture also increases,while the maximum bending tensile strain,residual stability,tensile strength ratio(TSR)and fatigue life(180℃)decrease,and the aging performance has the greatest influence on TSR of asphalt mixture.Considering the site construction temperature and durability of the asphalt mixture,the best mixing temperature of AC-20 is 180℃,and the storage time should not exceed 6.7 h.