Numerical Simulation of Soil Displacement and Settlement in Deep Foundation Pit Excavations Near Water

Advancing urbanization in China requires large-scale high-rise construction and underground transportation projects. Consequently, there is an increasing number of deep foundation pits adjacent to water bodies, and accidents occur frequently. This study uses a numerical simulation method to study the stability of the deep foundation pit near water based on the Biot three-dimensional seepage-stress coupling model, with the open-cut section on the south bank of the Jinan Yellow River Tunnel Project as the engineering field test. This indicates the following: (1) the maximum horizontal displacement of the diaphragm wall occurred in the fifth excavation stage, and a horizontal brace effectively controlled the inward horizontal displacement of the foundation pit; (2) considering the effect of seepage in the soft soil foundation, the maximum vertical displacement of the ground surface at each excavation stage occurred adjacent to the underground continuous wall. As the depth of the foundation pit increased, the vertical surface settlement decreases gradually in the direction away from the excavation face; (3) considering the seepage conditions, within each interval of excavation of the foundation pit, the horizontal displacement of the continuous underground wall and ground settlement declined; and (4) the numerical simulation and field monitoring data were in good agreement. Under the conditions of accurate model simplification and parameter selection, numerical simulations can adequately forecast conditions of the actual project.

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Numerical Simulation of Deep Foundation Pit Construction under Complex Site Conditions

Advances in Civil Engineering ◽

10.1155/2021/6669466 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Huifen Liu ◽

Kezeng Li ◽

Jianqiang Wang ◽

Chunxiang Cheng

Keyword(s):

Numerical Simulation ◽

Ground Surface ◽

Reference Value ◽

Horizontal Displacement ◽

Deformation Monitoring ◽

Deep Foundation ◽

Foundation Pit ◽

Deep Foundation Pit ◽

Ground Surface Settlement ◽

Stress And Deformation

Based on the deep foundation pit project of Laoguancun station of Wuhan rail transit line 16 and according to the engineering characteristics of the construction conditions and the site surrounding the environment, the method of combining field monitoring and finite element numerical simulation is adopted to analyze the law of stress and deformation of the deep foundation pit during excavation and support construction; it includes the horizontal displacement of the underground diaphragm wall, supporting axial force, and the ground surface settlement, which can be compared with measured data. Finally, some suggestions for monitoring and construction of the deep foundation pit in the subway station have been put forward and have certain reference value and practical guiding significance for the design and construction of similar engineering projects. The deformation monitoring of the retaining structure at the middle of the long side of the foundation pit should be strengthened during the construction process.

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Study on Composite Soil Nailing Wall in Soft Soil Area of Complex Condition with Emphasis on Analysis by Finite Element Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.174-177.2020 ◽

2012 ◽

Vol 174-177 ◽

pp. 2020-2023 ◽

Cited By ~ 1

Author(s):

Bing Wang

Keyword(s):

Finite Element ◽

Soft Soil ◽

Horizontal Displacement ◽

Deep Foundation ◽

Circular Area ◽

Foundation Pit ◽

Soil Nails ◽

Deep Foundation Pit ◽

Soft Soil Area ◽

Soil Area

Based on a typical projects, the horizontal displacement in depth, horizontal displacement and vertical subsidence of pile top, and settlements of surrounding buildings are monitored with the process on digging of deep foundation pit. The study on digging process of foundation pit is analyzed by using finite element software. Using mapped meshing method, from mixing the pile near the semi-circular area (radius = 50m), the meshing appropriate encryption in order to improve the accuracy of the external semi-circular area (radius = 65m) mesh is less appropriate sparse.Layer by layer to kill the layers of the soil unit and activate the soil nails (spring element), the simulated excavation and synchronization of soil nails construction.Verify the arc form of failure surface in side of deep foundation pit in soft soil area. Which is valuable for reference to similar structure engineering of foundation pit.

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Effect of Staged Excavation on Retaining Structure in Soft Soil Area

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.633 ◽

2012 ◽

Vol 170-173 ◽

pp. 633-636 ◽

Cited By ~ 1

Author(s):

Jie Liu ◽

Xin Guang Xu

Keyword(s):

Soft Soil ◽

Horizontal Displacement ◽

Structure Type ◽

Operating Conditions ◽

Deep Soil ◽

Deep Foundation ◽

Foundation Pit ◽

Deep Foundation Pit ◽

Retaining Structure ◽

Geological Conditions

Based on a deep foundation pit in Tianjin, the authors introduced the retaining structure type, surrounding conditions, and the geological conditions of proposed field. According to the engineering characteristics, the excavation was divided into three typical operating conditions. Based on the monitoring of staged excavation of deep foundation pit, analysis on horizontal displacement, deep soil displacement, column settlement and bracing axial force was carried out. The general rules of the deformation and internal force of retaining structures induced by staged excavation were given, which will provide the references for similar engineering.

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Metro Station Deformation Caused by Deep Foundation Pit Construction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.580-583.1061 ◽

2014 ◽

Vol 580-583 ◽

pp. 1061-1064

Author(s):

Chun Lei Xin ◽

Bo Gao

Keyword(s):

Numerical Simulation ◽

Three Dimensional ◽

Simulation Method ◽

Main Body ◽

Deep Foundation ◽

Foundation Pit ◽

Metro Station ◽

Deep Foundation Pit ◽

Construction Methods ◽

Transfer Station

Many excavation and backfill methods can be used to construct a deep foundation pit, but foundation pit construction will undoubtedly affects security of existing metro station. This research based on a transfer station of Chengdu Metro, three-dimensional numerical simulation method was used to analyze the deformation of metro station by changing construction methods of foundation pit. The results show that: (1) Both excavation and backfill methods of foundation pit have a significant effect on connection segments of metro station. (2) The main body of metro station is largely unaffected by foundation pit construction but it has been in the process of subsidence. (3) The more the construction steps of foundation pit are, the more slowly the displacement of metro station changes. The above results certainly contribute to research and develop new types of construction methods for complicated metro station.

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Numerical Simulation on a Deep-Foundation Pit of Shenzhen Holiday Plaza Project

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.937.433 ◽

2014 ◽

Vol 937 ◽

pp. 433-437

Author(s):

Yi Zheng

Keyword(s):

Numerical Simulation ◽

Simulation Model ◽

Engineering Application ◽

Horizontal Displacement ◽

Internal Force ◽

Deep Foundation ◽

Foundation Pit ◽

Strong Basis ◽

Deep Foundation Pit ◽

Wall Deformation

Based on test data of the prestressed anchor cable composite soil nailing wall deformation and internal force of structure of Shenzhen Holiday Plaza foundation pit, the numerical simulation model of foundation pit is established by FLAC3D software. Through the reasonable selection of soil constitutive model and structural unit, the numerical simulation model is consistent with the project practice. The simulation results on horizontal displacement of foundation pit, the internal force of the structure, the surface layer stress and damaged form are reasonable. This does not only provide a strong basis for the optimum design of the foundation pit, but also provide a scientific guidance for engineering application.

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Study on the Deformation Characteristics of Supporting System of Deep Foundation Pit in Subway Station Construction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.546 ◽

2011 ◽

Vol 243-249 ◽

pp. 546-551

Author(s):

Hua Zhi Zhang ◽

Yi Fang Feng

Keyword(s):

Numerical Simulation ◽

Horizontal Displacement ◽

Subway Station ◽

Deformation Characteristics ◽

Deep Foundation ◽

Foundation Pit ◽

Deep Foundation Pit ◽

Supporting System ◽

Simulation Results ◽

Metro Project

Taking Jiyu Bridge Station of Wuhan Metro Project as example, the deformation characteristics of supporting system of deep foundation pit was studied by means of numerical simulation (FLAC3D) in consideration of construction order. The deformation fields of different excavation depths of diaphram wall were obtained and analyzed in order to gain the maximum horizontal displacement value and settlement value. By comparison with the monitoring data, the simulation results can basically reflect the deformation characteristics. Moreover, the simulation results showed that the application of diaphram wall was feasible for foundation pit supporting in Jiyu Bridge Station, meanwhile, the results can be based on to guide the construction.

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Numerical Simulation And Monitoring Analysis Of Deep Foundation Pit In Shijiazhuang Area

E3S Web of Conferences ◽

10.1051/e3sconf/202128301046 ◽

2021 ◽

Vol 283 ◽

pp. 01046

Author(s):

Zhang Yu ◽

Yu Li ◽

Liu Weichao

Keyword(s):

Numerical Simulation ◽

Numerical Analysis ◽

Horizontal Displacement ◽

Hebei Province ◽

Analysis Method ◽

Deep Foundation ◽

Foundation Pit ◽

Deep Foundation Pit ◽

Fourth Section ◽

Control Range

The foundation pit engineering is a work with large amount of use and high difficulty coefficient. It is necessary to ensure the deformation of soil in the control range and the safety of the whole structure of the foundation pit. In this paper, the foundation pit support project in Shijiazhuang City, Hebei Province is taken as the research object, and the numerical analysis method is used to simulate the pile-anchor support in the First Section of the fourth section of the foundation pit. In this paper, the horizontal displacement value of deep foundation pit and the settlement value of the top edge of foundation pit are analyzed, It provides reference for future projects.

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Study on the Deformation of Supporting Structure for Foundation Pit in Strata with Rock-Soil Combination

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.446-449.1797 ◽

2012 ◽

Vol 446-449 ◽

pp. 1797-1803

Author(s):

Ai Jun Yao ◽

Xin Dong Zhang ◽

Xian Jun Zou

Keyword(s):

Numerical Simulation ◽

Engineering Design ◽

Horizontal Displacement ◽

Internal Force ◽

Lateral Deformation ◽

Deep Foundation ◽

Foundation Pit ◽

Deep Foundation Pit ◽

Supporting Structure ◽

Site Monitoring

Taking the deformation of row pile supporting structure of foundation pit in strata with rock-soil combination as the research target and taking an open cut metro deep foundation pit as an example, by in-site monitoring and numerical simulation, analyze the horizontal displacement of retaining piles and the change law of steel support axial force in the strata with rock-soil combination, and summarize the change law of row pile supporting structure in the process of excavation under the conditions of this strata, so that to provide experience and guidance for similar engineering design and construction. The results show that: the structure of foundation pit has obvious effects on deformation and internal force of supporting structure, the result obtained from numerical simulation fits well with the tendency of monitoring data changing. In which, the deformation of row pile supporting structure in the middle and upper part of soil strata is larger, the deformation of middle and lower part of soil strata is comparatively smaller, the lateral deformation of row piles to basement has a tendency of gradual decreasing by taking the interface of rock-soil as a boundary.

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