Mesoscopic Test Study of the Interface between Geogrid Transverse Rib and Sand

A series of pullout tests are carried out in different vertical pressure by using pullout model test equipment. Using image visual tracing technique to track the interaction process of the interface of the geogrid transverse ribs and sand, and the rule of interface particles movement is further studied through quantitative analysis. The results show that: The standard sand/transverse ribs upper interface region is about 10 times the average particles size, lower interface region is about 6 times the average particle size, in which the particles take place displacement and rotation during pullout process. The transverse rib interface maximum shear strain field along the pullout direction and the upper and lower areas take place expansion, forming a shear strain concentration zone, and are basically consistent with the transverse ribs pullout displacement field. The upper interface thickness is larger than the lower interface thickness, and with the normal pressure to increase, the interface thickness increased slightly.