基于汉堡车辙试验铁尾矿沥青混合料耐久性研究

Research on Durability of Iron Tailings Asphalt Mixture Based on Hamburg Wheel Tracking Test

通过正交试验设计了不同混合料类型、铁尾矿掺量、沥青用量和石灰用量的铁尾矿沥青混合料,采用浸水汉堡车辙试验分析了不同类型铁尾矿沥青混合料在高温和浸水条件下的耐久性,采用统计学方法提出了铁尾矿沥青混合料耐久性设计指标及标准.结果表明:混合料类型、铁尾矿用量、沥青用量和石灰用量均对铁尾矿沥青混合料的加载次数、轮辙深度和总变形速率D r具有不同程度的显著影响,且铁尾矿用量对耐久性影响最为显著.铁尾矿用量超过15%时,石灰用量低于1.5%时,混合料耐久性将产生显著降低.建议在高温和多雨环境下,铁尾矿沥青混合料应进行耐久性设计检验,且应满足加载次数不小于20000次,轮辙深度不大于10 mm,总变形速率D r不大于1.6 mm/h的技术要求.

Iron tailings asphalt mixtures with different mixture types,iron tailings content,asphalt content and lime content were designed by orthogonal test,and the durability of different types of iron tailings asphalt mixtures under high temperature and immersion conditions was analyzed by immersion Hamburg rutting test.The durability design index and standard of iron tailings asphalt mixture were put forward by statistical method.The results show that the type of mixture,the amount of iron tailings,asphalt and lime all have significant effects on the loading times,rutting depth and total deformation rate D r in different degrees,and the amount of iron tailings has the most significant effect on durability.When the amount of iron tailings exceeds 15%and the amount of lime is less than 1.5%,the durability of the mixture will be significantly reduced.It is suggested that the durability design test of iron tailings asphalt mixture should be carried out in high temperature and rainy environment,and the loading times should be no less than 20000 times,the rutting depth should be no more than 10mm,and the total deformation rate D r should be no more than 1.6 mm/h.