امین کشاورز

The ultimate seismic bearing capacity of strip footing resting on a granular soil slope and ?-c soil is studied in this thesis using the stress characteristics method considering two side failure surface mechanism. In this research, the pseudo-static method, conventional pseudo-dynamic method, and modified pseudo-dynamic method are applied to seismic analysis of bearing capacity of footing. First, using the boundary condition, the stress equilibrium equations along the positive and negative characteristics lines are solved, and then the stress state and slip lines patterns are defined. Finally, the ultimate bearing capacity of footing are determined using the stress state in the soil-footing interface. A computer code developed in MATLAB was used to calculate the seismic bearing capacity of footing using the stress characteristics method in conjunction with the seismic analysis. The results were presented as diagrams and graphs, and the effects of different mechanical and dynamic parameters such as soil friction angle, slop angle, normalized frequency, seismic acceleration coefficient, soil damping ration and etc., were assessed. The investigation of the results indicate that the seismic bearing capacity obtained using the modified pseudo-dynamic method is more critical than those of pseudo-static and conventional pseudo-dynamic methods.