Measured stress analysis of supporting structure under different excavation steps in deep foundation pit

作者：Zhu Dapeng; Qin Liangkai^*; Lin Yundian; Qu Honglue

来源：Electronic Journal of Geotechnical Engineering, 2014, 19(Z2): 10057-10070.

• Anchoring forces
• Deep foundation pit
• Deformation and stress
• Pre-stressed anchor
• Reinforcement stress
• Soil pressure
• Supporting structure
• Supporting systems

Taking the New Museum Foundation Pit Project at Chengdu for instance, based on the measured deformation and stress data of the pit and its supporting structureduring the process of the deep foundation pit excavation, this article analyzes the change law of the soil pressure behind the supporting pile, the anchoring force of pre-stressed anchor cable, and the reinforcement stress of the supporting pile body with the different excavationsteps. The research shows:(1) The supporting system comes into play a role with the excavating and supportingof the foundation pit, it weakens the stress of the soil body around the foundation pit. (2)The pre-stressed anchor cable owns active constraint mechanism. The anchoring force of the cable increases when the displacement of the anchoring rock mass enlarges.(3)The stress change curvesof reinforcement on eitherside of the pile bodyhave the feature of symmetry with pile, and the single curve is an inverted triangle that the upperpartis big and the lower part issmall.

• 出版日期2014