The use of improved radial movement optimization to calculate the ultimate bearing capacity of a nonhomogeneous clay foundation adjacent to slopes

摘要

Considering the nonhomogeneity of a clay foundation, the unilateral sliding failure mode is constructed and the constraint expression of the ultimate bearing capacity of a foundation adjacent to slopes is established based on the upper-bound limit analysis theorem. Calculation of the ultimate bearing capacity has transformed into the solution to the extreme value of the multidimensional objective function with a variable boundary. The improved radial movement optimization is applied to the search for the critical slip surface and the optimization calculation of the ultimate bearing capacity of a foundation adjacent to slopes on nonhomogeneous clay soil. Influence parameter analysis is performed. Through the comparative analysis of three examples, the optimization results indicated that IRMO had high feasibility, accuracy and stability for the calculation of the ultimate bearing capacity. A slope angle exceeding the critical value generated a failure mechanism with slope instability due to the gravity of the soil. Under the assumption that cohesion increased linearly with depth, the increase in soil nonhomogeneity produced a shallower critical slip surface, whereas the ultimate bearing capacity presented a linear increase. When the distance of the footing from the edge of the slope exceeded 5.2B(0), the ultimate bearing capacity tended to be constant.