scholarly journals Influence of Filter Tube of Pumping Well on Groundwater Drawdown during Deep Foundation Pit Dewatering

Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3297
Author(s):  
Xuehan Zhang ◽  
Xuwei Wang ◽  
Yeshuang Xu
Keyword(s):  
Tube Length ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Depth Difference ◽  
Groundwater Drawdown ◽  
Filter Tube ◽  
Optimal Values ◽  
Closed Pattern ◽  
The Impact

The partial penetrating waterproof curtain combined with pumping wells is widely applied to deep foundation pit dewatering engineering. The filter tube of the pumping well plays a critical role on the environment effect that resulted from foundation pit dewatering. This paper investigated the impact of the filter tube on the groundwater drawdown outside the pit to provide a theoretical basis for the foundation pit dewatering design. Three patterns according to the relative position of the waterproof curtain and the filter tube, which are called wall-well patterns, namely the full-closed pattern, part-closed pattern, and none-closed pattern, have been analyzed. By taking a practice engineering case in Shanghai as an example, the relationship among the proportion of the filter tube length to the dewatering aquifer thickness, the buried depth difference of the wall-well, and the groundwater drawdown difference at both sides of the waterproof curtain are discussed by numerical simulation. The full-closed pattern is the optimal wall-well pattern on the ideal condition. The suggested and optimal values of the filter tube length to the dewatering aquifer thickness are 38.7% and 58.2%. The suggested and optimal values of the buried depth difference of the wall-well are −6.41 m and −1.92 m.

scholarly journals Analytical Study on Dynamic Response of Deep Foundation Pit Support Structure under the Action of Subway Train Vibration Load: A Case Study of Deep Foundation Pit of the New Museum Near Metro Line 2 in Chengdu, China

2015 ◽  
Vol 2015 ◽  
pp. 1-10
Author(s):  
Zhu Dapeng ◽  
Qin Liangkai ◽  
Lin Yundian
Keyword(s):  
Dynamic Response ◽  
Support Structures ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Vibration Load ◽  
Vibration Loads ◽  
Subway Train ◽  
The Impact ◽  
Train Vibration

Presently, foundation pit support structures are generally regarded as the temporary structures and the impact of vibration loads is often overlooked. As opposed to static and seismic loads, the vibration loads of subway trains are a type of cyclic load with a relatively long duration of action and a definite cycle; it is of great importance for the design of foundation pit support structures to correctly evaluate the impact of subway train vibrations on deep foundation pit and support works. In this paper, a dynamic three-dimensional numerical model is built that considers the vibration load of subway trains on the basis of the static numerical model for deep foundation pit support structures and simplified train loads to study the impact of train vibrations on deep foundation pit and permanent support structures. Studies have shown that the dynamic response of surface displacement mainly occurs in the early period of dynamic load, the vibration load of subway trains has little impact on ground subsidence, the support pile structure is in an elastic state during dynamic response under the action of subway train vibrations, and the action of train vibration loads is inimical to the safety of foundation pit support structures and should be closely studied.

The Impact on the Surrounding Buildings of a Deep Excavation in Hefei

2014 ◽  
Vol 1021 ◽  
pp. 96-99
Author(s):  
Jia Yang Wang ◽  
Xiao Qiang Wang
Keyword(s):  
Residential Building ◽  
Deep Excavation ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Whole Process ◽  
Timely Feedback ◽  
Station Base ◽  
The Impact ◽  
Settlement Monitoring

According to the building settlement monitoring around the base pit, research the deep base pit excavation impacting on the surrounding buildings. Take Hefei subway station base pit project as example, by way of an adjacent residential building whole process of excavation monitoring, research the impact of deep excavation on the surrounding buildings. Timely feedback to the construction unit, to ensure the smooth construction of pit, and provides a reference to design and construction of deep foundation pit.

Numerical Simulation of Pumping Well-Underground Concrete Wall-Recharging Well in Dewatering of Deep Foundation Pit

2012 ◽  
Vol 446-449 ◽  
pp. 1764-1768
Author(s):  
Jian Xiu Wang ◽  
Pei Wang ◽  
Dong Chang Sui
Keyword(s):  
Numerical Simulation ◽  
Numerical Method ◽  
Zhejiang Province ◽  
Concrete Wall ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Proper Position ◽  
Deep Foundation Pit ◽  
Pumping Wells ◽  
Filter Tube

With the foundation pit of south air shaft nearby Qiantang River, Subway No.1, Hangzhou, Zhejiang province as an example, the interaction between pumping wells and underground concrete wall, together with the soft curtain formed by recharging wells are simulated with numerical method. The results indicate that the proper position of filter tube of pumping well to underground concrete wall can reduce the drawdown outside pit, and the drawdown outside pit can be reduced by recharging curtain.

Research on the Influence of Deep Foundation Pit Excavation on Neighboring Buildings

2014 ◽  
Vol 1055 ◽  
pp. 131-134
Author(s):  
Wen Jing Chai
Keyword(s):  
Construction Projects ◽  
Deep Excavation ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Excavation Process ◽  
Technological Level ◽  
Deep Foundation Excavation ◽  
Management Staff ◽  
The Impact

With the development of society and economy, China's investment in construction projects is increasing, which requires the construction and management staff to improve their professional level, to develop a more scientific construction plan to ensure construction quality, and ultimately to the construction goal. Especially in deep foundation excavation process, it not only needs to upgrade the technological level of the excavation, but also needs to enhance the impact of researches on the approaching buildings to make the appropriate preparations to reduce adverse effects on the surrounding buildings, which meets the actual needs of construction, to ensure building construction safety. By exploring the impact of deep excavation on adjacent buildings, the paper makes the construction workers deeply understand the importance of deep foundation construction work.

Simulation Analysis on Deep Foundation Pit Construction Near the History Style Construction

2013 ◽  
Vol 671-674 ◽  
pp. 113-116
Author(s):  
Chun Yuan Liu ◽  
Wei Wei Cao ◽  
Yu Liu
Keyword(s):  
Simulation Analysis ◽  
Horizontal Displacement ◽  
Construction Safety ◽  
Calculation Model ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Engineering Construction ◽  
Deep Foundation Pit ◽  
The Third ◽  
The Impact

Based on the impact of deep foundation pit excavation to the adjacent history style construction, FLAC3D was adopted to establish the excavation and supporting calculation model of a pit in Tianjin. The excavation deformation was analyzed, and the contact slip effect of the supporting structure and soil was considered. The results of study are as follows. (1) The pit has been dig to the third layer, and the values calculated are consistent with the monitored ones by comparing simulation values and measured results on B1 section. (2) Digging to the bottom of the pit, we can predict the biggest horizontal displacement of soil is 34.6 mm, and the value is 11.2mm in the history style construction. Therefore, the results of the study can play a guiding role in the engineering construction safety.

Simulating Effect of Anchor Cable Pre-Tension to Supporting Structure

2013 ◽  
Vol 788 ◽  
pp. 525-529
Author(s):  
Tao Wang ◽  
Ren Wang Liang
Keyword(s):  
Bending Moment ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Cost Performance ◽  
Deep Foundation Pit ◽  
Supporting Structure ◽  
Anchor Cable ◽  
Steel Strand ◽  
The Impact ◽  
Free Section

Since the pre-stressed anchor technology became to be used from the beginning of twentieth century, it is widely used with the advantages of its good applicability, high cost performance, good looking appearance and easy green. Pre-stressed anchor achieves the purpose of actively controlling foundation pit deformation by exerting pre-stress on steel strand of its free section. This thesis chooses deep foundation pit engineering, adopt Mohr-Coulomb ideal soil body by finite difference software FLAC3D, and select different anchor pre-tension values to simulate. It combines Lizheng software to do numerical simulation and analytic study on pile-anchor supporting structure. This thesis compares results coming from the two kinds of software, and analyze the impact on row piles' body bending moment, pile top deformation, anchor cable axial force and foundation pit deformation when pre-tension changes.

scholarly journals Analysis of Seepage Characteristics of a Foundation Pit with Horizontal Waterproof Curtain in Highly Permeable Strata

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1303
Author(s):  
Chenghua Shi ◽  
Xiaohe Sun ◽  
Shengli Liu ◽  
Chengyong Cao ◽  
Linghui Liu ◽  
...  
Keyword(s):  
Hydraulic Conductivity ◽  
Theoretical Calculation ◽  
Calculation Method ◽  
Design Method ◽  
Water Pressure ◽  
Water Inflow ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Seepage Characteristics

At present, jet-grouted horizontal waterproof curtain reinforcement has become an essential method for deep foundation pit groundwater control. However, there is still a lack of an effective theoretical calculation method for horizontal waterproof curtain reinforcement, and there is little research on the seepage laws of foundation pits under different horizontal waterproof curtain conditions. Based on Darcy’s seepage theory, theoretical analysis models of deep foundation pit seepage were established considering the effect of a horizontal curtain in a highly permeable formation. Through the established models, the calculation method of the water inflow and the water pressure under the condition of a horizontal curtain was derived. Then through indoor tests, the reliability of the theoretical calculation method was verified. Furthermore, the established theoretical calculation method is used to analyze the influence of various factors on the water inflow and the water pressure, such as the ratio of hydraulic conductivity of the horizontal curtain to surrounding soil, thickness, and reinforcement position of the horizontal curtain. It is found that the hydraulic conductivity ratio has the most significant influence on the seepage characteristics of the foundation pit. Finally, the design method was applied to an example of the horizontal waterproof curtain of the foundation pit, which is located at Juyuanzhou Station in Fuzhou (China). The water inflow per unit area is 0.36 m3/d in the foundation pit, and this implies that the design method of the horizontal waterproof curtain applied for the excavation case is good and meets the requirements of design and safety.

Mechanical Analysis of Enclosure Pile under Different Constraints

2011 ◽  
Vol 90-93 ◽  
pp. 485-489
Author(s):  
Li Guo ◽  
Peng Li He ◽  
Guang Jun Zhang
Keyword(s):  
Mechanical Analysis ◽  
Subway Station ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Retaining Structure ◽  
Cantilever Structure ◽  
Reinforcement Measures

The enclosure pile is extensively used as retaining structure in the foundation pit excavation. And it is always combined with other reinforcement measures. So it is unreasonable to a certain degree that the enclosure pile is analyzed as cantilever structure. Taken the deep foundation pit of a subway station in Hefei for instance, the effect of other reinforcement measures on restrained conditions of enclosure piles in the paper was taken into account. And the behavior of enclosure pile under various restrained conditions was analyzed. Based on that, some helpful suggestions for practical retaining structure of foundation pit were put forward.

Simulation of Excavation Process for Deep Foundation Pit Base on Nonlinear Finite Element Theory

2015 ◽  
Vol 744-746 ◽  
pp. 579-583
Author(s):  
Hui Min Wang ◽  
Zhen Jian Ji ◽  
Liang Cao ◽  
Ji Yao ◽  
Shan Guang Qian
Keyword(s):  
Finite Element ◽  
Safety Evaluation ◽  
Nonlinear Finite Element ◽  
Distribution Law ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Simulation Research ◽  
Deep Foundation Pit ◽  
Excavation Process ◽  
Element Theory

Deep Pit is the main content of modern urban geotechnical engineering. In this paper, based on a deep foundation pit engineering as an example, based on the nonlinear finite element theory, conduct a numerical simulation research for foundation pit excavation process. Obtained the distribution law of pit deformation, stress distribution and the supporting structure of the internal forces, under the various processes. These provide a theoretical basis for safety evaluation of foundation pit engineering.

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