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International Journal of Engineering Technology and Construction, 2021, 2(3); doi: 10.38007/IJETC.2021.020303.

Construction Monitoring and Numerical Simulation of the Foundation Pit in the Upper Subway Tunnel

Author(s)

Guoxiang Cheng

Corresponding Author:
Guoxiang Cheng
Affiliation(s)

Liaoning Shihua University, Fushun, China

Abstract

With the rapid development of China's urbanization construction, the demand for land has gradually increased. In order to save land, people have begun to develop and utilize underground space, so that the foundation pit project has ushered in a new era of development. More and more common. However, in the deep foundation pit engineering of subway stations, the surrounding environment of the foundation pit has become more and more complicated, and the excavation depth of the foundation pit is also getting larger and larger, which makes the construction and design more difficult, The issue of stability is becoming increasingly prominent. Based on the above background, in order to ensure the safe construction operation and the stability of the foundation pit, the research content of this paper is to monitor the foundation pit in real-time on-site, and carry out experimental simulation on the construction site of the upper foundation pit of a Shenzhen subway tunnel. Under various working conditions of foundation pit excavation, the monitoring of the supporting structure can timely detect the deformation and stress of the supporting structure and surrounding buildings to predict the development trend of deformation, so that the deformation and displacement of the supporting structure are controlled within the allowable deformation Within the scope, to ensure the safety and stability of the foundation pit.Nowadays, the numerical simulation technology is well used in foundation pit engineering. Through numerical simulation, we can understand the deformation mode of foundation pit excavation more intuitively, and analyze the displacement and force changes of the supporting structure. The experimental results show that the foundation pit supporting structure composed of cast-in-place piles is more conducive to the stability of the foundation pit than the graded grading excavation; the maximum cumulative horizontal displacement of the two is -36.3mm and -42.4mm, respectively; as the foundation pit is opened During the excavation, the axial force of the steel support will increase first and then decrease. When the excavation approaches the bottom, the support axial force will stabilize; the deep horizontal displacement of the cast-in-situ pile support structure gradually increases with the excavation of the foundation pit. By comparing and analyzing the laws of simulation and monitoring values, the feasibility of the numerical simulation method is verified, which provides a basis for the design of foundation pit support schemes, the selection of construction methods, and the deployment of monitoring points.

Keywords

Foundation Pit, Construction Monitoring, Numerical Simulation, Support Measures

Cite This Paper

Guoxiang Cheng. Construction Monitoring and Numerical Simulation of the Foundation Pit in the Upper Subway Tunnel. International Journal of Engineering Technology and Construction (2021), Vol. 2, Issue 3: 30-46. https://doi.org/10.38007/IJETC.2021.020303.

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