Effective use of geosynthetics to increase bearing capacity of shallow foundations

In this research, a reinforcement mechanism for shallow foundations is determined through laboratory model tests and numerical analyses. The numerical analyses are performed with the finite element program FEMtij-2D using the elastoplastic subloading t(ij) model. The frictional behavior between the reinforcement and the ground is simulated using an elastoplastic joint element. Several tests were performed whereby the installation depth, length, roughness, and fixity conditions at the edges of the reinforcement were varied. Results show that the effectiveness of the reinforcement and the bearing capacity of the reinforced ground depend on the position, length, roughness, and fixity condition of the reinforcement. A significant increase in the bearing capacity can be achieved if the geosynthetics are properly placed at an optimum length with the boundary fixed to the ground. The effect of the loading position is also investigated because in reality the load on a foundation does not always act at the center of the foundation. The numerical results accurately describe the experimental results; the simulations accurately account for the mechanical behaviors of both the soil and reinforcement and the frictional behavior between them. Therefore, the simulation technique can be used to predict the bearing capacity of reinforced ground.