Quantitative Research on the Properties of Expansive Sliding-Zone in Eastern Jilin Province

The paper presents experimental studies performed on a natural sliding-zone soil evolved by expansive soft rock. Five undisturbed samples and three disturbed samples were obtained from Xinyan landslide zone in Yanbian, Jilin, China. Initially, this study was based on laboratory experiments, including physicochemical tests and swelling tests. A scanning electron microscope was employed to investigate the microfabric of sliding-zone soft rock. Two specimens from each sample, representing the horizontal and vertical planes, were tested. In addition, a quantitative analysis of microstructure was studied by MATLAB programming software and the WD-5 image processing system. Given the difficulty of describing the exact complexity of soft soil pore morphology, box counting dimension was extracted to represent the fractal feature of pore structure. The study shows that the change of microstructure is a biggest reason for the strength decrease of sliding-zone. Identifying structural characteristics is conductive to understanding the failure mechanism of expansive soft rock.