泡沫沥青冷再生混合料沥青路面永久变形预估研究

Study on Permanent Deformation Prediction of Foamed Asphalt Cold Recycling Mixture Asphalt Pavement

针对国道滨州港—榆林公路阜城—武邑段养护改造工程,通过击实试验、劈裂强度试验、动态模量试验等室内试验和数值计算,进行了泡沫沥青冷再生混合料配合比设计及沥青路面永久变形预估等工程应用研究。研究结果表明:泡沫沥青冷再生混合料的配合比设计为铣刨料82. 5%、石粉16%、水泥1. 5%,最佳泡沫沥青用量2. 5%,最佳含水率6. 3%,其马歇尔稳定度和冻融劈裂强度比性能检验满足技术要求;阜武公路泡沫沥青冷再生混合料的动态模量为2 431MPa;考虑全年温度分布频率、轴载等级分布频率基于线性叠加原理提出沥青路面永久变形预估方法,该预估方法可模拟沥青路面结构全温域受力过程,准确预估其容许永久变形寿命。经计算,阜武公路的容许永久变形寿命为10年。

According to the maintenance and renovation project to Fucheng-Wuyi section of national highway Binzhou Port-Yulin Highway,the engineering application research of the mixture ratio design of asphalt cold recycling mixture and permanent deformation prediction of asphalt pavement is carried out through laboratory tests such as compaction test,split strength test and dynamic modulus test and numerical calculation.The results show that the mixture ratio design of foamed asphalt cold recycling mixture is the milling material 82.5%,stone powder 16%and cement 1.5%,the optimum foamed asphalt dosage 2.5%,optimum moisture content 6.3%,Marshall stability and freeze-thaw splitting strength ratio test performance meet the technical requirements;dynamic modulus of foamed asphalt cold recycling mixture of Fucheng-Wuyi Highway is 2 431 MPa.Considering the annual temperature distribution frequency and axle load grade distribution frequency,based on the linear superposition principle,a method for predicting the permanent deformation of asphalt pavement is proposed,the prediction method can simulate the whole temperature domain stress process of asphalt pavement structure,whose allowable permanent deformation life is accurately predicted.By calculation,the allowable permanent deformation life of Fucheng-Wuyi Highway is 10 years.