Abstract: Since the mechanical behavior of the convex corner is complex due to surcharge near the excavation, it is of great importance to evaluate the influence of changes in strut position on the convex corner. Field monitoring and numerical simulations were used to analyze the influence law of the changes of strut position on the deformation and stress characteristics of the convex corner area. The axial force of inner strut, the lateral earth pressure on the pile, the horizontal displacement of the pile, the settlement of adjacent building and the bending moment of the pile were obtained. The research results show that the depth of strut position that is too high or too low is unfavorable to the coordinated deformation and the force of the retaining system. In contrast, the optimal strut position in this analysis is between 0.33 and 0.50 times the depth of the excavation (0.10–0.33 times the depth of the pile).

Key words: deep foundation pit, convex corner, strut position, surcharge