M. Jahanandish - Dept. of Civil Engineering, Shiraz University, Shiraz, Iran.
A. Keshavarz, - Dept. of Civil Engineering, Shiraz University, Shiraz, Iran.

In this paper the zero extension line method has been used for evaluating the static and dynamic bearing capacity of foundations. If friction and dilation angles are equal, the results would be similar to that obtained from the stress characteristics method. By starting from the boundary and computing the boundary stresses and applying equilibrium equations in finite difference form along the zero extension lines, one can obtain the zero extension line net and calculate the field parameters in passive, Goursat and active zones and compute the stresses at each point of the net. Therefore, the critical load acting at the boundary can be computed. Having the horizontal and vertical pseudostatic earthquake coefficients, the dynamic conditions may also be analized. Nondimensional and standard graphs have been presented for getting the critical load, which can bring the foundation to collapse. The effects of horizontal and vertical earthquake coefficients, dilation angle and friction angle have also been considered. It has been concluded that in non-associative soil it is better to consider the effect of dilation angle. Otherwise, the analysis would not be conservative

Bearing capacity, Zero Extension Lines, Stress characteristics, Strip foundations