基于高温性能的MS-III微表处混合料级配优化设计 Optimization Design of Gradation for MS-III Micro-Surfacing Based on High Temperature Performance

微表处以其优良的使用性能和显著的社会经济效益，在公路养护中有着广泛的应用。本文在4.75 mm~9 mm筛孔之间增加了7 mm筛孔，以便于更好的控制大粒径的级配；在微表处混合料配合比初步设计的基础上，采用正交设计法制定出9种不同的级配方案，研究集料的堆积状态对微表处混合料高温性能的影响。结果表明，级配对微表处混合料的高温性能有着较大的影响，而且7 mm筛孔对微表处的毛体积相对密度和马歇尔稳定度有着显著的影响；推荐出了最佳级配的确定方法——最大振实堆积密度法，并给出了基于微表处高温性能的最优级配及级配范围，可供需要考虑高温稳定性要求的气候区进行配合比设计使用。 With its good performance and remarkable social and economic benefits, Micro-surfacing has a broad application in highway maintenance repair. Through contrastive analysis of the conventional grading at home and abroad, 7 mm mesh is increased between 4.75 mm and 9 mm mesh for grading control. Based on the preliminary design method of micro-surfacing, we used 9 orthogonal design methods to study the effect of aggregate accumulation on the high temperature performance of micro-surfacing mixtures. The results showed that gradation had a great influence on the high temperature performance of the mixture, and the 7 mm mesh had a significant effect on the bulk volume density and the Marshall stability. This paper not only proposed method—the maximum tapped bulk density method to determine optimum gradation, but also gives the optimal grading and grading range based on the high temperature performance of micro-surfacing, in order to provide a reference for the climatic zone that need to consider high temperature stability.