基于CT图像的AC-13C型沥青混合料冻融损坏细观结构分析

Microstructure analysis of freeze-thaw damage of AC-13C asphalt mixture based on CT image

空隙率及空隙结构会影响沥青混合料的稳定性和耐久性。以AC-13C型沥青混合料为研究对象,综合运用X-Ray CT扫描技术和Mimics图像处理方法,分析了沥青混合料在冻融循环作用下的细观结构以及内部空隙变化情况。混合料的空隙率和空隙数量随冻融循环次数的变化规律为:初始呈单调增加趋势,随着冻融循环次数的增加,增幅变缓。三维重构后,混合料空隙率和空隙数量及尺寸沿试件纵向的变化规律为:试件两端空隙数量少,空隙尺寸大且形成的空隙率大;中间部分空隙数量多,空隙尺寸小且形成的空隙率小。该研究成果可为沥青路面减轻冻融损害和提高路用性能提供方向。

Void ratio and void structure affect the stability and durability of the asphalt mixture.In this paper,AC-13 C asphalt mixture was taken as the research object,and X-Ray CT scanning technique and Mimics image processing method were used to analyze the microstructure and internal void variation of asphalt mixture under freeze-thaw cycle.The results show that the voidage and the number of voids change with the number of freeze-thaw cycles:initially the increase is monotonous,and with the number of freeze-thaw cycles increasing,the increase slows down.After three-dimensional reconstruction,the variation of voidage and the number and size of voids along the longitudinal direction of the test piece are as follows:the number of voids at both ends of the test piece is small,the void size is large and the voidage formed is large,and the number of voids in the middle portion is large,the void size is small and the void ratio formed is small.The research results provide a direction for asphalt pavement to reduce freeze-thaw damage and improve road performance.