EXPERIMENTAL STUDY ON TRIANGULAR APERTURE GEOGRID-REINFORCED BASES OVER WEAK SUBGRADE UNDER CYCLIC LOADING

Abstract

The objective of this study is to investigate the behavior of triangular aperture geogrid-reinforced bases over weak subgrade under cyclic loading through laboratory testing. Behavior of unpaved structures, such as permanent displacement, percentage of resilient displacement, stress distribution, and modulus variation were investigated. Nineteen large-scale laboratory cyclic plate loading tests were conducted on unpaved sections with three different base course thicknesses. Three types of triangular aperture geogrids were selected to reinforce the bases respectively. The results indicated that the triangular aperture geogrids effectively reduced permanent displacement and maximum vertical stress, distributed the load wider and more uniformly, increased the modulus of the base, and reduced the degradation rate of the base course. Generally, the performance of the specific geogrids tested in this study, all of which are from the same family of geogrids, improved as the level of robustness, unit weight, rib thickness, and mechanical properties increased.