The Analysis Of Pile-Anchor Support System In Foundation Pit

In this paper, cantilever and pile-anchor support system of foundation pit are analyzed by ANSYS which is the large-scale general finite element analysis software, getting the stress and displacement of foundation pit and support system. Combined with a foundation pit project in Handan, on the basis of the FEA analysis, traditional methods are adopted to design and calculate the foundation pit support. Compared with the two results, testified the ANSYS' suitability in analyzing cantilever and pile-anchor support of the foundation pit.As for the foundation pit project in Handan, the paper list four methods to support it: soil-cement retaining wall support, cantilever support, pile-anchor support, soil nail wall support. After calculation, pile-anchor support and soil nail support is suitable for the project. The paper adopted different traditional methods to design the foundation pit support separately, calculating the displacement and stress of the pile and stress of the anchor and soil nail wall.After finishing the design of the traditional methods, ANSYS software is adopted to analysis cantilever support and pile-anchor support system. The soil layers are simplified into two layers because of difficult convergence of the program. During the process of FEA analysis, first of all, the initial stress is calculated, then it is introduced in the analysis when the birth and death element is used to simulate the excavation of the foundation pit and the contact element are adopted to simulate the contact surface of the pile and soil, finally, considering the construction load, and then run the program and get the results.On the basis of calculation and analysis above, the displacement and soil pressure are compared with each other. the two different methods get the similar results which testified the ANSYS' suitability in analyzing cantilever and pile-anchor support of the foundation pit, offering the reference for future design of foundation pit. The paper also analyzed the main parameters which effect the level displacement of the support system.