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Exploration of Deep Foundation Pit Support Scheme for Super High-Rise Buildings with "Two Walls in One, Two-Way Support System" in Complex Subway Environments

Author(s)

Su Gao*, Xiangyang Chen, Hua Mei, Yanjing Ma, Jin Xu, Ruihong Li, Jin Li

Affiliation(s)

College of Building and Engineering, Nantong Vocational University, Nantong, Jiangsu, China *Corresponding Author.

Abstract

In order to solve the problem of deep foundation pit support for existing super high-rise residential buildings with complex surrounding environments and high protection requirements, such as subway entrances and exits, subway section tunnels, and river channel relocation culverts and pipelines, we explore the use of an underground continuous wall "double wall combined with four reinforced concrete supports" setting scheme, and adopt a first level deep foundation pit support scheme combining diagonal braces and braces. Based on the selected plan, 10 typical soil profiles and 1 underground connecting channel profile around the foundation pit were selected. According to 17 working conditions, the elastic foundation beam theory was used, and the internal force values, displacement, overall stability safety factor, wall bottom anti uplift safety factor, and pit bottom anti uplift safety factor of the underground continuous wall, support and plate were calculated using Qimingxing V8.2. The calculation structures of different profiles were compared and analyzed, and some were verified using Lizheng Deep Foundation Pit 7.0. The calculation results of the two software were in good agreement and could meet the requirements of the specifications. The calculation conclusions and support schemes of the article provide numerical references for similar deep foundation pit projects.

Keywords

Near Subway Deep Foundation Pit; Support Technology; Underground Continuous Wall; Reinforced Concrete Support; Internal Force Calculation; Safety Factor

References

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