Developing a prediction model for segment joint opening in an underwater shield tunnel

For in-service metro shield tunnels in soft soils, large circular deformations are a major concern because they usually lead to various problems, such as water leakage, joint openings, and concrete cracks. However, the monitoring of circular deformation depends mainly on manual surveying, and the automatic monitoring methods developed in recent years generally have low economic applicability and are not widely implemented. In this study, an automatic and cost-effective system was presented to monitor circular deformation in shield tunnels by using only inclinometers. Experiments were conducted to prove the assumption that each segment can be regarded as a rigid body and to investigate the position of the joint rotation center. Then, a method for monitoring circular deformation based on the rigid body and plane section assumptions was proposed. The joint opening angle, maximum joint opening width, horizontal diameter convergence, and bolt strain were calculated from rotation angles of segments which can be monitored directly by inclinometer. A case study was conducted for a section of a metro shield tunnel with an ongoing pit excavation nearby. The rotation of segments was measured using MEMS inclinometers, and the data were transmitted using ZigBee and general packet radio service (GPRS) wireless communication technology. Results show that the proposed system could be implemented to improve transportation safety in relevant situations and similar conditions.

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Measuring joint opening displacement between model shield-tunnel segments for reduced-scale model tests

Structures ◽

10.1016/j.istruc.2018.09.003 ◽

2018 ◽

Vol 16 ◽

pp. 112-118 ◽

Cited By ~ 2

Author(s):

Jie Wang ◽

Hongqing Liu ◽

Huabei Liu

Keyword(s):

Model Tests ◽

Scale Model ◽

Shield Tunnel ◽

Opening Displacement ◽

Joint Opening ◽

Reduced Scale

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Analysis and Prediction of Long-term Settlement of Metro Shield Tunnel in Saturated Sand

10.21203/rs.3.rs-315813/v1 ◽

2021 ◽

Author(s):

Jianzheng Liu ◽

Yang Yixin ◽

Yang Chunjie

Keyword(s):

Prediction Model ◽

Sandy Soil ◽

Shield Tunnel ◽

Sand Layer ◽

Saturated Sand ◽

Subway Tunnel ◽

Curve Model ◽

Engineering Projects ◽

Soil Area

Abstract based on the existing monitoring data, this paper uses the matured data method to analyze and predict the long-term settlement of the subway shield tunnel, and comprehensively analyzes the long-term settlement of the subway shield tunnel in the saturated sand layer of Zhengzhou. Logical curve model is used. Etc. separately predict the long-term settlement of the Zhengzhou metro shield tunnel, and combine the prediction results to summarize the characteristics of the prediction model to obtain a prediction model suitable for the long-term settlement of the subway shield tunnel in the sandy soil area represented by Zhengzhou, which can be used for the operation of the Zhengzhou subway tunnel. Management and similar engineering projects provide a certain reference basis.

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Long-Term Evolution of Joint Leakage and Joint Opening for Shield Tunnel in Soft Soils Deep under Seabed

KSCE Journal of Civil Engineering ◽

10.1007/s12205-021-0492-0 ◽

2021 ◽

Author(s):

Wenfeng Zhou ◽

Shaoming Liao ◽

Yanqing Men

Keyword(s):

Long Term Evolution ◽

Shield Tunnel ◽

Soft Soils ◽

Joint Opening ◽

Term Evolution

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Bending Behavior of Segmental Joint Structure of Under-River Shield Tunnel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.446-449.2132 ◽

2012 ◽

Vol 446-449 ◽

pp. 2132-2138 ◽

Cited By ~ 1

Author(s):

Kun Feng ◽

Chuan He ◽

Jun Wang ◽

Chun Qi ◽

Si Jin Liu

Keyword(s):

Mechanical Characteristics ◽

Bending Stiffness ◽

Shield Tunnel ◽

Concrete Cracking ◽

Failure Characteristics ◽

Joint Opening ◽

Joint Structure ◽

Key Factor ◽

Bending Behavior ◽

Full Scale Tests

The bending stiffness of segmental joints is the key factor which affects the mechanical characteristics of shield tunnel. In this paper, full-scale tests and numerical analysis were carried out to study the bending stiffness, joint opening variation and failure characteristics of segmental joint structure for under-river shield tunnel. The results showed the bending stiffness and joint opening behaving non-linear significantly. And the concrete cracking and bolt breaking were detected in the tests.

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Influence of Segment Design of Shield Tunnel on the Magnitude of Joint Opening

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.698 ◽

2010 ◽

Vol 160-162 ◽

pp. 698-703

Author(s):

Yin Liu ◽

Hong Wei Huang ◽

Dong Mei Zhang

Keyword(s):

Analytical Solution ◽

Mechanical Model ◽

Tunnel Lining ◽

Shield Tunnel ◽

Flexural Stiffness ◽

Water Leakage ◽

Joint System ◽

Joint Opening ◽

Influence Mechanism

It is obviously a simplification to consider the tunnel lining as uniformly permeable.In reality it is more likely that there are specific leaks assocoated with segmental lining joints. In the case of in situ concrete linings, construction joints can provide leakage paths, accounting for most of the water leakage. In this paper, based on the mechanical model of segment joint, the analytical expression of magnitude of joint opening was developed, in light of which, the occurrence of water leakage through the joint system can be judged. Taking the metro line No.1 in Shanghai as an example, effects of such parameters as joint flexural stiffness, bolt location, bolt stiffness, bolt prestress, etc. on the magninitude of the joint opening were analyzed respectively through the analytical solution. The results not only help us realize the influence mechanism of segment design on the magnitude of joint opening of the segmental linings, but also provide the guidance for waterproof design of the shield tunnel.

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Research on displacement prediction of shield tunneling through existing tunnel based on LSSVM

E3S Web of Conferences ◽

10.1051/e3sconf/202123703034 ◽

2021 ◽

Vol 237 ◽

pp. 03034

Author(s):

Xianguo Wu ◽

Tiemei Zeng ◽

Yanyan Tao ◽

Hongyu Chen

Keyword(s):

Prediction Model ◽

Horizontal Displacement ◽

Shield Tunnel ◽

Shield Tunneling ◽

Displacement Prediction ◽

Deformation Control ◽

Bottom Level ◽

Soil Storage ◽

Sample Data ◽

Day By Day

The construction scale of the shield tunnel underpass is expanding day by day. In order to study the safety influence and deformation control of the shield tunnel underpass on the existing tunnel, the LSSVM model is established. Based on the collected soil storage pressure, foam volume, simultaneous grouting volume and other six shield construction parameters and corresponding sample data of the tunnel bottom displacement, the horizontal displacement and settlement displacement of the existing tunnel bottom caused by the approach construction are predicted. Taking a subway project as an example, the research results show that the prediction model of shield tunneling under the existing tunnel bottom level and settlement displacement has strong generalization ability and rapid and accurate prediction effect. This method can provide reference for similar projects.

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A structural health monitoring system for data analysis of segment joint opening in an underwater shield tunnel

Structural Health Monitoring ◽

10.1177/1475921719876045 ◽

2019 ◽

Vol 19 (4) ◽

pp. 1032-1050 ◽

Cited By ~ 3

Author(s):

Xuyan Tan ◽

Weizhong Chen ◽

Guojun Wu ◽

Luyu Wang ◽

Jianping Yang

Keyword(s):

Structural Health Monitoring ◽

Linear Regression ◽

Multiple Linear Regression ◽

Real Time ◽

Monitoring System ◽

Health Monitoring ◽

Water Pressure ◽

Shield Tunnel ◽

Joint Opening ◽

Health Monitoring System

The opening of segment joints is considered critical for the stability analysis of a shield tunnel lining. In order to prevent tunnel disasters, an integrated framework was developed in this study based on the laboratory experiment, real-time monitoring, and statistic theory. As a case study, this presented method was employed in a typical underwater shield tunnel to prevent leakage disasters. The water pressure experiment was used to analyze the importance of joint openings for the tunnel waterproofing. Then, an automatic structural health monitoring system was installed in the study site to have real-time monitoring of segment joint opening and the variation of external load applied to the structure. Based on the monitoring data, a multiple linear regression model was developed to explain the response of joint opening to water pressure and temperature at the important positions of arch crown, spandrel, and hance of the tunnel. The multiple linear regression results were verified to be in agreement with those of the numerical simulation; they denote that (1) joint opening decreased with the rise in temperature, but increased with the rise in water pressure at arch crown and hance, and (2) the segment joint opening decreased with the rise in water pressure at spandrel. As a potential application, the developed model was applied to predict future behaviors of structure, which is vital to prevent disasters and provides a reference to underwater constructions.

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