多聚磷酸复合改性沥青混合料的路用性能

Pavement Performance of Polyphosphoric Acid Composite Modified Asphalt Mixtures

采用重复蠕变恢复试验分析了多聚磷酸对基质沥青、SBS及SBR改性沥青抗变形恢复能力的影响,并通过贯入剪切试验、半圆弯拉试验及弯曲疲劳试验评价了多聚磷酸对基质沥青混合料、SBS改性沥青混合料及SBR改性沥青混合料抗剪切性能、低温抗裂性能及疲劳性能的影响,采用Weibull分布分析了不同沥青混合料在不同失效概率下的疲劳性能.结果表明:多聚磷酸的掺入显著增加了沥青的黏度,对其弹性变形恢复能力贡献较小,而SBS改性剂可大幅度提高沥青的弹性变形恢复能力;多聚磷酸能够明显改善沥青混合料的高温抗剪稳定性;通过复配SBS或SBR改性剂,可有效弥补多聚磷酸对沥青混合料低温性能的负面影响;多聚磷酸对沥青混合料的疲劳性能也有一定程度的改善.

The effect of polyphosphoric aeid（PPA） on elastic deformation recovery ability of matrix as- phalt, SBS and SBR modified asphalts was analyzed by repeated creep recovery test. Through penetration shear test, semi-circular bending test and fatigue bending test, the pavement performance of matrix asphalt mixture, SBS and SBR modified asphalt mixtures was studied. Finally, the fatigue properties of different asphalt mixtures were analyzed by Weihull distribution at different failure probabilities. The results show PPA can significantly increase the viscosity of asphalt, and PPA has less influence on the elastic deforma- tion recovery ability of asphalt, but SBS can greatly improve the elastic recovery of asphalt; PPA has a sig- nificant effect in improving shear-stability at high temperature; The negative effect of PPA on the low tem- perature performance of asphalt mixture can be[2 -3] effectively compensated by compositing SBS or SBR, and PPA can increase to a certain extent anti-fatigue properties of asphalt mixtures.