PULLOUT STIFFNESS CHARACTERISTICS OF GEOGRID ENBEDDED IN WELL-GRADED GRAVEL

Abstract

In this study, pullout tests of geogrid embedded in well-graded gravel were performed, in order to establish the design procedure of GRS integral bridge which was proposed as a new type of bridge abutment using reinforced-soil method. The pullout tests were focused on the effect of confining pressure and stiffness of geogrid on the pullout stiffness characteristic of geogrid. The experiments revealed that the pullout stiffness was largely affected by the confining pressure. This is due to the increase of friction and inter-rocking resistance mobilized between the geogrid and the gravel as well as the decrease of free length of geogrid. The pullout stiffness of geogrid was also affected by the relative displacement between the geogrid and the gravel.