Active earth pressure calculation considering the influence of intermediate principal stresses

retaining walls;  Breaking the norms;  active earth pressure;  plane strain;  Intermediate principal stress

Under plane strain conditions, the expression forms of Matsuoka Moto-Nakai Teruo failure criterion, Lade-Duncan failure criterion and Yu Maohong double shear unified strength criterion were derived, and the soil shear strength index under plane strain condition and conventional triaxial compression condition was linked. On this basis, the active earth pressure calculation formula considering the influence of intermediate principal stress is obtained. The calculation shows that as long as the internal friction angle of the filled soil is greater than 0, the active earth pressure value considering the influence of the intermediate principal stress is smaller than the Rankine active earth pressure value, but the calculation results differ greatly depending on the failure criteria.