Abstract:The anti-uplift stability of pit bottom is often used as the control condition of the build-in depth of enclosing structure in the soft soil regions. The influence of pit width on the uplift stability is not considered in the current industry standards, which leads to the overlarge insertion depth of retaining components in the design of the narrow strip foundation pit project in the deep, thick and soft soil regions and results in waste. The practical foundation pit engineering has the obvious spatial effect. By analyzing the influence of pit width effect on the anti-uplift stability of pit bottom, the classification standards of foundation pit based on the width are obtained. The calculation method of the anti-uplift stability at the bottom of narrow strip foundation pit is put forward. It is showed that the narrow strip foundation pit has the good anti-uplift stability, and its stability is analyzed and verified through the engineering cases. Finally, the parametric sensitivity analysis of the influencing factors on the anti-uplift stability at the bottom of narrow strip foundation pit is carried out. The study results complement and improve the standard formula, and provide the basis for the design of narrow strip foundation pits in the soft soil regions.
