Loosening earth pressure considering progressive development of soil arching

The calculation of the earth pressure on the structure is important for the design and construction of pipe jacking. Due to the ground loss, the arching effect caused by the relative slip between interfaces can relieve the vertical earth pressure. Based on the Terzaghi model, the equilibrium differential equation is established through the principal stress rotation analysis, and the influences of depth and ground loss on the shape of failure plane are studied. The equation is solved under the boundary condition of the initial state and the steady state. Compared with the previous studies, the proposed method is reasonable. According to the actual situation in pipe jacking construction, the effects of the dilatancy angle and friction angle on the arching effect are explored. The results show that the dilatancy angle of the soil has an important influence on the initial shape of the failure surface, and the friction angle affects the stress state and shear strength of the soil, which may provide a reference for the calculation of loosening earth pressure in pipe jacking construction.