The elasto plastic model proposed by Li and Dafalias (2000) was used for the simulation of the behaviors of sand along various loading paths. Li and Dafalias model includes density and pressure dependencies using the state parameter:Ψ=e-e_c, where e_c is the reference void ratio on e_c-log p at the critical state. The model performance along various loadings paths were examined with an emphasis on the evolution of the state parameter, which includes stain ratio constant paths and those simulating the behavior of gentle slopes subjected to the inflow of pore fluid. The conventional stability conditions of the model along various loading paths were evaluated and discussed by using the state parameter. The effect of initial anisotropy was introduced into Li and Dafalias model through the modified stress method. The performance of Li and Dafalias model was found to be satisfactory, though some modifications are necessary for better simulations.