关键词: 道路工程;水泥稳定碎石;微裂技术;自愈合;裂缝宽度;微观结构

Abstract: To make a quantitative and ocular analysis of the self-healing property of micro-cracks based on the microstructure of cement stabilized macadam,the changes of the width of micro-cracks and the generation of healing products with the increase of age at different levels of micro-cracks were monitored by the digital crack width monitor KON-FK(B) in real time and observed and analyzed by the universal stereo microscope XTZ-0ST.With the descriptive statistics function of SPSS software,the processing and statistical analysis of the width of micro-cracks were completed.As a result,ranges of micro-cracks' width before and after self-healing were concluded.Based on the principle of pixel area calculation method,images of the self-healing products as age increased were further processed and analyzed by the image processing software Imagemagick.And after the calculation,the coverage of self-healing products in different periods and logarithmic fitting equation of the pattern of the coverage at different levels of micro-cracks were concluded.The results show that micro-cracks' width of cement stabilized macadam gradually reduces with the increase of age and the coverage of self-healing products which are generated inside micro-cracks constantly enlarges.And in the later stage micro-cracks basically realize a complete healing.It proves that cement stabilized macadam after micro-cracks occur has a good capacity of self-healing in therms of both macroscopic mechanical properties and micro-structural characteristics.

Key words: road engineering;cement stabilized macadam;micro-crack technology;self-healing;crack width;microstructure