Analysis of internal force and displacement of foundation pit pile anchor supporting structure based on soil frost heaving

Abstract

In order to study the influence of soil frost heaving on the internal force and displacement of foundation pit supporting structure in seasonal frozen soil area in Northwest China, the field test of pile anchor supporting structure for deep foundation pit is carried out to monitor the change of internal force and displacement of supporting pile in winter. The interaction relationship between soil frost heaving and internal force and displacement of supporting pile is analyzed combined with temperature change conditions. The results show that: Under the condition of natural frost heaving in winter, the frost heaving effect is the most significant at 0.5 m of the upper part of the supporting pile, and the reinforcement stress value on both sides of the pile body is the largest. The change rate of bending moment of supporting pile above 3.25m is higher than that of the embedded section and the maximum bending moment is at 0.5m, while the blot has a certain constraint on the bending moment deformation. The displacement of supporting pile increases in proportion to the freezing time, and the final increase is 157.7% of the initial value. It can be seen that soil frost heaving has great influence on the internal force and deformation of the upper structure of the retaining pile. The research results can provide reference for the construction of foundation pit support engineering in similar areas in winter.