Determination of seismic bearing capacity of strip foundation based on the unified strength theory

Based on the unified strength theory which takes the effect of intermediate stress into consideration,by supposing composite curved rupture surfaces and employing pseudo-static approach and the method of limit equilibrium,the result of static,seismic bearing capacity of strip foundation is obtained.The comparative analysis shows that in the light of static bearing capacity of strip foundation,the bearing capacity coefficients will be improved in varying degrees when the method considering the unified strength theory is employed.That proves the bearing capacity coefficients obtained by the present way of calculation is smaller than real values.While in terms of seismic bearing capacity,under the operation of seismic loading,N_(cd) changes little(2%～6%)while N_(qd) and N_(γd) reduce by 20%～75%,the seismic bearing capacity is 15%～40% less than the static bearing capacity.