高速公路中双层乳化沥青厂拌冷再生基层的应用

基于对符合再生要求的材料充分回收利用,节约资源、降低排放及减少传统半刚性基层沥青路面反射裂缝的理念,G30连霍高速郑洛段大修改建工程将传统的半刚性基层替换为偏柔性的双层乳化沥青厂拌冷再生基层结构,通过全新的双层乳化沥青厂拌冷再生路面结构设计、沥青混合料回收料(RAP)性能分析、乳化沥青厂拌冷再生配合比设计、现场取芯与弯沉检测性能验证及乳化剂性能改善,确定并验证了最佳路用性能下的混合料生产配合比。结果表明:当0~10 mm RAP掺量32%,10 mm~30 mm RAP掺量43%,0~5 mm石屑掺量12%,10 mm~30 mm碎石掺量13%,乳化沥青用量4.1%,水泥用量1.8%,最佳含水率为5.2%时,混合料路用性能最佳,其15℃劈裂强度达0.625 MPa;双层乳化沥青厂拌冷再生基层结构对沥青混合料回收料利用率高、经济效益明显。

Based on the concept of recycling materials that meet the requirements of fully recycling,saving resources,reducing emissions and reducing reflective cracks in the traditional semi-rigid base layer asphalt pavement,the major reconstruction project of the Zhengluo section of G30 Lianhuo Expressway replaces the traditional semi-rigid base layer with a flexible factory-mixed cold recycling base structure of double-layer emulsified asphalt.Through the new factory-mixed cold recycling of double-layer emulsified asphalt pavement structure design,Reclaimed Asphalt Pavement(RAP)performance analysis,factory-mixed cold recycling of emulsified asphalt mix ratio design,on-site coring and deflection detection performance verification and emulsifier performance improvement,the mix ratio for optimal road performance is determined and verified.The results show that when the 0~10 mm RAP material dosage is 32%,the 10~30 mm RAP material dosage is 43%,the 0~5 mm stone chip dosage is 12%,the 10~30 mm gravel dosage is 13%,the emulsified asphalt dosage is 4.1%,the cement dosage is 1.8%,and the optimal moisture content is 5.2%,the mixed material road performance is the best,and its splitting strength at 15℃reaches 0.625 MPa.The factory-mixed cold recycling base structure of double-layer emulsified asphalt has a high utilization rate and obvious economic benefits for reclaimed asphalt pavement.