集料粉尘含量对沥青混合料路用性能的影响研究

Research on Influence of Aggregate Dust Content on Road Performance of Asphalt Mixture

为了研究粉尘含量对沥青路面材料使用性能的影响,按照《公路工程集料试验规程》(JTG E42—2005)的要求,从现有集料中筛出小于0.075 mm的颗粒,分别制备了(占0~3 mm料)10.5%、12.5%、15%、18%四种粉尘含量的Sup 20型沥青混合料,成型Sup 20型沥青混合料试件,并测试其体积指标及路用性能指标。结果表明:当粉尘含量超过12.5%后,沥青混合料的空隙率、矿料间隙率、饱和度不满足规范要求;粉尘含量超过18%后,混合料的劈裂强度比、残留稳定度衰减至临近规范下限:动稳定度衰减17.80%,60 min时的车辙深度已超过2 mm,低温性能衰减12.13%。

In order to study the impact of dust content on the road performance of asphalt mixtures,particles smaller than 0.075 mm were sieved from the existing aggregates according to the“Test Methods of Aggegate for Highway Engineering”(JTG E42—2005).10.5%,12.5%,15%,18%four types of Sup 20 asphalt mixture with dust content(0~3mm material ratio),forming Sup 20 type asphalt mixture specimens;testing volume index and road performance index.The results show that when the dust content exceeds 12.5%,the void ratio,mineral gap ratio,and saturation of the asphalt mixture do not meet the specification requirements;when the dust content exceeds 18%,the split strength ratio and residual stability of the mixture decay to approaching the lower limit of the specification:the dynamic stability is attenuated by 17.80%,the rutting depth at 60 min has exceeded 2 mm,and the low temperature performance attenuated by 12.13%.