New Theoretical And Numerical Simulation, For The Ultimate Bearing Capacity Of Square Footings

At present, the ultimate bearing capacity of square shallow foundation is often solved with Prandtl-Vesic correction formula. Prandtl-Vesic of ultimate bearing capacity of strip foundation belongs to the plane strain problems, which adopt step superposition method to obtain the formula of ultimate bearing capacity. However, the correction formula for the square shallow foundation does not consider the mechanical space effect of the foundation and the lateral earth pressure to cutting body.Although the ultimate bearing capacity of square shallow foundation belongs to the space problem, some scholars simplied the steps of their research and the lateral earth pressure between the foundation soil was ignored, which had lead to imperfect stress analysis in the solution process.Based on the limits equilibrium theory, square shallow foundation was cut out a quarter along diagonal lines of the surface to analysis, considering the weight, cohesion and overload, but also the lateral earth pressure to the cutting body, then this paper solved the ultimate bearing capacity with the overall analysis.The foundation ultimate bearing capacity factor was smaller than Hansen value, but larger than Prandtl value and Terzaghi value by comparing and analyzing with them when the friction angle belowed 25°. It would produce the moment deflecting from the outer edge of base and decrease the foundation ultimate bearing capacity because the paper considered the lateral earth pressure. The result showed that the result possessed relatively high reference value. Finally, this paper simulated the square rough shallow foundation on the application of ADINA, then got the ultimate bearing capacity of different soil samples and the factors of soil bearing capacity for one samples. Compared with the results of the formula of this paper, they met good agreement, which verified the correctness of this paper's new solution theory.