Calculation of active earth pressure on external corners with equal length on both sides in excavation engineering

Taking the external corner with equal lengths as the research object, two failure modes of the equilateral external corner are established, and the active earth pressure calculation formula of the equilateral external corner in the limit state is further deduced when the external angle is 90°. The comparison between the theoretical calculation results and Midas/GTS simulation results shows that when the ratio of the side length B to the depth H is large, the sliding wedge failure will occur at the external corner, and the active earth pressure of the external corner in the range of wedge-shaped slider will not change with the change of size B. When the ratio of the side length B to the depth H is small, the displaced soil is composed of two parts, and the earth pressure varies with the change of size B. In this paper, the magnitude and distribution law of the active earth pressure obtained by the horizontal micro-layered limit equilibrium analysis method is similar to the three-dimensional simulation value of the Midas/GTS software, which can prove the feasibility and rationality of the theoretical calculation.