Simplified Method for Estimating the Inner Support and Internal Force through Stand Column Uplift of Foundation Pit in Soft Soil

Abstract

In the excavation process of Foundation Pit in Soft Soil area, it will cause the large uplift of stand column, and may cause the instability and failure of foundation pit in case of being serious; but the additional internal force of support system caused by the uplift and sinking of stand column currently has no practical calculation model in the foundation pit design. This article discusses the reason and mechanism for uplift of stand column in the foundation pit, proposes the simplified calculation method of estimating the additional bending moment of inner support through uplift of stand column in allusion to two main influence factors of bottom heave and vertical load caused by the excavation of foundation pit, inversely calculates the permissible additional bending moment of inner support based on this, verifies by combining the monitoring data for uplift of stand column in the actual project, and finally, further proposes the project measures corresponding to the uplift of stand column, hoping to provide beneficial reference for the similar project.