Finite Element Analysis of Square Footing Resting on Geosynthetic Reinforced Soil

Abstract

Using different types of reinforcing layers such, metallic (non-extensible -steel) and non-metallic (extensible -geosynthetic) to improve the bearing capacity of weak soil is studied. Many researchers have studied the effect of using reinforcing layers to predict the improvement occurred in weak soil under static load [1]-[5]. Most of these studies are on strip or circular footing. But, square footing is a common shape that used in foundations systems; however, some researchers studied it [6]-[11]. The behaviour of strip footing resting on geosynthetic reinforced sand is studied under cyclic loading [12]. ABSTRACT Bearing capacity of soil is considered an important parameter at which the soil can resist loads above it. Different ways are used to improve the bearing capacity of weak soils. One of the used techniques is the soil reinforcing technique. In this study, the results of numerical simulations on square footings resting on geosynthetic reinforced sand are presented. In order to predict the improvement in the bearing capacity resulting from the usage of the reinforcing layers in the sand, finite element analysis package ANSYS is used. Nonlinear Drucker-Prager's model is used as material model to simulate the soil and Linear Isotropic model is used as material models to simulate the reinforcing layers and the footing respectively. SOLID45 element is used as element type to simulate the soil and the footing and Link8 is used as element type to simulate the reinforcing layers. Numerical model of 150mm x 150mm x 25mm is used to simulate the square footing and model of 900mm x 900mm x 600mm is used to simulate the soil. Under the effect of both static and dynamic loading two main effective parameters are discussed in this study. The investigated parameters are the number of the reinforcing layers and the depth of the reinforced zone which includes the variation of spacing between the reinforcing layers. The bearing capacity improvement investigation is analyzed.