Study on the Performance of Foundation Pit Supporting System Considering the Process of Anchor Recycling

Abstract

The technology of recoverable anchors / cable greatly avoids the disadvantage of traditional anchors / cable, such as non-recyclable, waste of resources and occupy underground space. However, there are many problems existed in the development, design and application processes. Taking a foundation pit project in the city of Jinan as an example, the numerical analysis of the whole construction processes was conducted to study the mechanical behaviour of supporting systems. It is found that the supporting pile has major deformation during the excavation and anchors recycle. For the process of anchor recycle, the bending form of supporting pile transformed from outward to inward. Moreover, the horizontal displacement of pile top increased by 21.4%. The axial force of upper anchor increased during the recycle of lower anchor, for example, the axial force of uppermost anchor increased by 21.3% comparing to the state that no anchor was recycled. Therefore, for the real project of anchor recycling, the internal force redistribution and deformation property of supporting system should be fully considered, to avoid the influence to the surrounding buildings and the foundation pit itself.