Study on the selection of inner diameter in shield tunnel segment in soft soil stratum

In order to calculate earth pressure in working chamber, three calculation modes which corresponding to status of elastic balanced, active limit equilibrium and passive limit equilibrium of the soil on the excavation face was built. The relationship of relative displacement between the soil in the chamber and the soil on the excavation face of shallow EPB shield tunnel was analyzed based on Rankines earth pressure theory. The threshold of chamber earth pressure values which correspond to the limit states of subsidence and upheaval were deduced and the reasonable range of the values were obtained. Combined with a shield tunnel construction practice, the theoretical and measured values are compared. The results show that the theoretical equations are valid and can provide a theoretical approach for the selection of chamber earth pressure.

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SEGMENT CRACKS AND ALIGNMENT ISSUES FOR TUNNELING CONSTRUCTION

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2014.34 ◽

2014 ◽

Vol 1 (1) ◽

Author(s):

Arulampalam Paul Suyanthiran

Keyword(s):

Tunnel Boring Machine ◽

Shield Tunnel ◽

Proper Selection ◽

Tunnel Boring ◽

Twin Tunnel ◽

Shield Tunnelling ◽

Tunnel Alignment ◽

Selection Of ◽

Left Lead

This study describes the causes of shield tunnel segment cracks and alignment issues during shield tunnelling. The study was conducted in Down Town Line 3 (DTL3) contracts 926 and 927 twin tunnel projects in Singapore. It is revealed that these issues arose when Tunnel Boring Machine (TBM) shoving on curve alignment though TBM is designed with articulation, which allows the machines to handle tight curves with ease. The study focused on how construction methodology affects the quality of tunnelling in terms of alignment and segment cracks. It was found that the clearance between the tail shield and tunnel lining was not maintained during mining. As a result, the tail shield exerts stress on the segments and causes cracks. In addition, the tunnel alignment deviated from pre-designed alignment, which directly affects the safety and durability of the shield tunnel. This study concludes that a proper selection of ring type “right lead” or “left lead” and the appropriate key selection, along with the skill of the workers, significantly solve segment cracks and alignment issues.

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Influence of pressure of sealed medium, inner diameter, and materials on selection of initial gasket width

Chemical and Petroleum Engineering ◽

10.1007/s10556-013-9734-4 ◽

2013 ◽

Vol 49 (3-4) ◽

pp. 251-255

Author(s):

V. D. Prodan ◽

A. V. Vasil’ev ◽

A. S. Dubinina

Keyword(s):

Inner Diameter ◽

Selection Of

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Analysis of the Longitudinal Settlements of Tunnel with the Soft Layers in Substratum Soil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.461.510 ◽

2012 ◽

Vol 461 ◽

pp. 510-512

Author(s):

Qian Yang

Keyword(s):

Finite Element ◽

Soft Soil ◽

Element Model ◽

Linear Functions ◽

Shield Tunnel ◽

Soft Layer ◽

3D Finite Element ◽

Operation Conditions ◽

Calculation Results ◽

Coulomb Model

The 3D finite element model on the interactions between soil and lining was established based on the Mohr-Coulomb Model. Different operation conditions were used to analyze influence on shield tunnel settlement in soft soil, such as difference in properties of substratum soil of tunnels. The deformation discipline of tunnels was achieved. The calculation results show that: the maximal settlement is linear functions of the elastic modulus of the soft layer.

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Effect of the Inhomogeneity of a Substratum Soil on Longitudinal Settlements of a Shield Tunnel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.568.129 ◽

2012 ◽

Vol 568 ◽

pp. 129-133

Author(s):

Qian Yang ◽

Jun Xing Zhang ◽

Geng Ning Zhang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Elastic Modulus ◽

Soft Soil ◽

Shield Tunnel ◽

Soft Layer ◽

Element Analysis ◽

3D Finite Element ◽

Longitudinal Length ◽

Coulomb Model

In this paper, we perform a 3D finite element analysis for the longitudinal settlement of a shield tunnel in soft soil, where a substratum soil contains a soft layer. The Mohr-Coulomb model is used for the substratum soil and soft layer. The longitudinal settlements are calculated for different elastic modulus and longitudinal length of the soft layer. The results show that a softer and longer layer will result in the larger settlement. It is also found that the maximum of the longitudinal settlements is linear function of the elastic modulus of the soft layer.

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Ứng dụng phương pháp nội suy Kriging khảo sát sự phân bố tầng đất yếu tuổi Holocene ở khu vực nội thành thành phố Hồ Chí Minh = Applying Kriging to predict the distribution of the holocene soft soil stratum in the ur

Science and Technology Development Journal ◽

10.3125/jstd.v10i2.400 ◽

2007 ◽

Vol 10 (2) ◽

Author(s):

San Hà Thị Phan ◽

Sơn Minh Lê

Keyword(s):

Soft Soil ◽

Soil Stratum ◽

The Holocene

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Influence of Values of Angle of Jet-joining on Non-uniformity of Water Inflow Along the Path in Pressure Collector-Pipeline

Proccedings of 10th International Conference "Environmental Engineering" ◽

10.3846/enviro.2017.073 ◽

2017 ◽

Cited By ~ 1

Author(s):

Volodymyr Cherniuk ◽

Vasyl Ivaniv

Keyword(s):

Experimental Investigation ◽

Initial Segment ◽

Terminal Segment ◽

Water Inflow ◽

Pressure Pipeline ◽

Inner Diameter ◽

Selection Of

Results of experimental investigation of the influence of values of the angle  at which jets join a pressure pipeline on the non-uniformity of water inflow along the collector-pipeline (CP) are presented. The inner diameter D of the CP is 11.28 mm, and the diameter d of the nozzles is 4.83 mm, d / D  0.428. Five CPs in which all the nozzles had been installed at angles  , the latter was given the values of:  0 ;  45 ;  90 ;  135 ;  180 , where investiguated. A CP in which in the initial segment the nozzles had been installed at the angle    0 , and in the middle and terminal segment    180 has been also investigated. The greatest non-uniformity of the water inflow along the CP was obtained for CPs with    90 , and the least one for CPs with diffrent values of the angle  . The obtained results give us the reason to conclude that it is possible to adjust the non-uniformity of water inflow into a CP by means of the method of selection of different values of angle  at which the jets join the CP.

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