Changes in Interface Strsses During Pullout Tests on Geogrid Strip Reinforcement

摘要

For a strop geogrid reinforcement, pullout resistnace per unit width is known to increase with decreasing specimen width at low applied normal stresses. This phenomenon can be explained by a conceptualized model for a pullout interaction mechanism consisting of combined 2-D and 3-D interaction mechanisms, and the results obtained from laboratory pullout tests can be extended to the field. In this paper, a series of pullout tests on stiff extruded geogrid specimens embedded in dense sandy gravel was carried out and the normal stresses at the soil-reinforcement interface were measured by small-diameter earth pressure cells. ON the basis of these tests, the fundamentlal behavior of soil-geogrid reinforcement interaction is explained and the conceptualized pullout interaction model is corroborated.