EFFECTS OF TRANSVERSE RIBS ON PULLOUT RESISTANCE AND DEFORMATION DURING THE UNLOADING-RELOADING PROCESS

Abstract

It is considered that the pullout resistance is more affected by the transverse elements than the longitudinal elements. In this study a square and a circle opening type and a plate are tested of pullout resistance in Toyoura sand during the unloading-reloading process through a series of laboratory model tests. The results show that unloading-reloading process reduces the pullout resistance of both two types of geogrid and a plate at peak value and at the residual part. But the pullout resistance of the square geogrid type in this study is decreased more as well as less stable than that of the other two. Moreover, the square geogrid type takes larger displacement to reach to the peak values of pullout resistance than the circle and plate ones do. To discuss the effects, all of the deformation of soil around geogrid is observed while it is pulled out. The PIV analysis shows the mechanism and effects of transverse ribs on the pullout resistance.