玄武岩纤维再生沥青混合料配合比设计方法分析

Analysis of mixture ratio design method of basalt fiber recycled asphalt mixture

再生沥青混合料中掺入玄武岩纤维,并应用马歇尔设计方法对掺有玄武岩纤维的再生沥青混合料进行配合比设计,确定了高RAP掺量(45%)下再生沥青混合料的最佳油石比及玄武岩纤维最佳掺量。试验结果表明,由于RAP料沥青老化,若仅使用90号新沥青将其再生,RAP最大掺量不应超过30%;由于RAP粗集料粒径产生变化(粒径细化,粗集料在使用和再生过程中有破碎现象),在配合比设计时应予以考虑。

Basalt fiber is added into recycled asphalt mixture,and Marshall design method is used to design the mix proportion of recycled asphalt mixture with basalt fiber. The optimum oil-stone ratio and basalt fiber content of recycled asphalt mixture with high RAP content（ 45%） are determined. The test results show that the maximum RAP content should not exceed 30% if only 90 new asphalt is used to regenerate RAP asphalt due to aging of RAP asphalt,and the mix proportion should be considered in the design of RAP coarse aggregate because of the change of particle size（ fine particle size,broken coarse aggregate in use and regeneration process）.