Evaluation of the Main Factors Influencing the Behavior of Strip Footings on Geogrid Reinforced Soils

Soils reinforced by geogrids exhibit different behavior, compared to unreinforced soils, due to having high tensile strength elements. In this paper, the main factors influencing the behavior of such reinforced soil under a strip footing are investigated and discussed. A numerical model for the reinforced soil is developed using FLAC-2D finite difference software. The model is calibrated, and then different important factors such as width, number, distance and depth of the first layer of geogrid are studied and evaluated. The qualitative behavior of the reinforced soil under different conditions of reinforcement elements is also studied in this work. The results of several analyses show that the optimum depth of the first layer of geogrid is one fourth of the footing width, and the other layers would have effective role up to 1.75 times of the width. Also, the distance between geogrid layers needs to be decreased in case of increasing their number, whose optimum value is less than half of the footing width. The geogrid width and its tensile strength have considerable effect on the behavior of the reinforced soil, when geogrid layers are in optimum position.