RESEACH ON ULTIMATE BEARING CAPACITY OF REINFORCED FOUNDATION BASED ON TERZAGHI THEORY ON ULTIMATE BEARING CAPACITY OF FOUNDATION

In order to study the effect of reinforcement on the bearing capacity of foundation, the limit equilibrium method and slice method were adopted for calculating the ultimate bearing capacity of reinforced foundation in non-cohensive soil based on Terzaghi ultimate bearing capacity theory.The slip blocks of foundation were divided into the active zone, transition zone and passive zone, in which the angle δ₁ between the side of the active zone and horizontal plane was not a fixed value but could meet the minimum prinicple of the bearing capacity of the foundation at failure. The sliding surface of the transition zone assumed to be a logarithmic spiral was divided into many triangular slices in calculation. The reinforcement was equivalent to tensile forces acting on the blocks. Based on the limit equilibrium theory, the force equilibrum formulas on the passive zone, active zone and transition zone were established,which could calculate the angles of δ₁ corresponding to the ultimate bearing capacity of foundation. By optimizing δ₁, the minimum bearing capacity of foundation could be calculated. The effects of the layers of being reinforced, embedment, spacing, length and internal friction angles on the bearing capacity of foundation were also analyzed. By comparison with experimental data, the feasibility of the method was verified.