scholarly journals Computational Model of Outer Circle and Inner Ellipse Shield Tunnel Lining Structure

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Shuancheng Gu ◽  
Guanlin Sun ◽  
Peili Su
Keyword(s):  
Calculation Model ◽  
Tunnel Lining ◽  
Shield Tunnel ◽  
Internal Space ◽  
Design Elements ◽  
Outer Circle ◽  
Force Method ◽  
Lining Structure ◽  
Tunnel Lining Design ◽  
Subway Tunnels

Subway tunnels are mostly located in strata with an uneven pressure. This uneven pressure is usually manifested by lateral pressure coefficients less than 1. To adapt to the unevenness of the stratum load, in this study, we propose a new shield tunnel lining structure—outer circle and inner ellipse shield tunnel lining structure—whose outer contour remains circular and the inner contour shape of the structure is designed according to the load conditions. We used the stiffness step discounting method to obtain the calculation coefficients used in the force method formulas and established the calculation model of the outer circle and inner ellipse shield tunnel linings. The force method was then used to determine the force distribution characteristics of the outer circle and inner ellipse shield tunnel lining structure. During the verification, it was sufficient to analyze whether the waist structure rigidity met the safety conditions. This simplifies the design elements. The internal space area of our proposed design is expanded by 0.86 m2 compared to the internal space area of the equal stiffness shield tunnel lining design.

Numerical Simulation on the Stress and Strain of Lining Structure with Double Shield Tunneling Construction

2012 ◽  
Vol 605-607 ◽  
pp. 2425-2429
Author(s):  
Feng Wang ◽  
Tie Jun Cui
Keyword(s):  
Ground Surface ◽  
Calculation Model ◽  
Tunnel Lining ◽  
Concrete Lining ◽  
Shield Tunnel ◽  
Tunnel Construction ◽  
Three Dimension ◽  
Shield Tunneling ◽  
Deformation Law ◽  
Lining Structure

This paper takes the Section 201 of shield construction engineering in Dalian Metro Line 2 as an example to analyze the deformation law of surrounding soil and the tunnel lining structure stress during shield tunnel construction. The shield tunnel construction is simulated dynamically by ADINA and the shield tunnel structure model of the concrete lining is established. This model is a three-dimension nonlinear finite element calculation model concerned with the grouting soil and original state soil. Taking the soil lithology in the upper layer and interact influences, we analyzed the dynamic process of shield construction, soil grouting and lining supporting and the stress distribution in difference reinforced concrete supporting segments and the ground settlement characteristics. Through numerical analysis method to study the deformation law of soil surrounding tunnel and the stress in tunnel lining, we get the results to compare with the results of Peck formula under the same condition. After generating the conclusions, we can provide several suggestions for shield tunneling construction, lining segment design and control of the ground surface settlement during the construction.

Effect of Time-Varying on Shield Tunnel Lining Structure

2014 ◽  
Vol 580-583 ◽  
pp. 987-990
Author(s):  
Feng Jun Liu ◽  
Jun Fang Chen
Keyword(s):  
Design Theory ◽  
Aging Effect ◽  
Tunnel Lining ◽  
Shield Tunnel ◽  
Time Varying ◽  
Bending Rigidity ◽  
Concrete Shrinkage ◽  
Lining Structure ◽  
Long Time ◽  
Internal Forces

In order to survey the time-varying effect on shield tunnel lining structure, rigidity reduce in the Homogeneous Ring Design Theory is introduced. There are three methods to evaluate the rigidity reduction caused by the aging effect. The first is the bending rigidity analysis method, which considers that the bending rigidity changes with the time-dependent stress and strain. The second is the method named the equivalent moment of inertia; the last is aging coefficient method. With the Homogeneous Ring Design Theory, the internal forces and displacement of the shield tunnel segment lining can be calculated. Based on the preliminary results, using the 1st method, the reduced rigidity and the long-time displacement at different instants of time can be calculated. It is found that the concrete shrinkage and creep effect can’t be ignored in the segment design. The survey is beneficial to monitor the deformation of tunnel lining, and the maintenance of the segments. It will make the tunnel work steadily and safely during the using period.

Study on Numerical Analysis of Tunnel Longitudinal Uneven Settlement Base on Elastoplastic Theory

2012 ◽  
Vol 446-449 ◽  
pp. 596-600
Author(s):  
Shou He Wu ◽  
Zhong Li ◽  
Si Yang Chen
Keyword(s):  
Longitudinal Design ◽  
Three Dimensional ◽  
Shell Element ◽  
Calculation Model ◽  
Tunnel Lining ◽  
Vertical Force ◽  
Tunnel Structure ◽  
Lining Structure ◽  
Element Type ◽  
The Impact

The stratum uneven settlement of tunnel is main factors that cause damage of tunnel longitudinal structure. a 3d numerical model is established for the force and deformation calculation of tunnel structure based on the elastoplastic theory. In the model, soil material is elastoplastic, and its constitutive model is Mohr Coulomb, the element type of soil is a three-dimensional solid, the element type of tunnel lining structure is space shell element, and tunnel settlement joint is three-dimensional linear spring. Calculation shows that, this calculation model is able to fully consider the impact of tunnel uneven settlement in all factors, and can simulate the vertical force and deformation behavior of tunnel structure in complex ground formation conditions. Research conclusion gives the vertical force and deformation of the tunnel structure under the condition of the stratum uneven settlement. It is very important reference for the longitudinal design and calculation of the tunnel lining structure.

Reliable Design and Study on Highway Tunnel Lining Structure

2014 ◽  
Vol 580-583 ◽  
pp. 1398-1401
Author(s):  
Ze Lin Niu ◽  
Yan Bo Qi ◽  
Jie Sheng Huang ◽  
Chao Wang ◽  
Jun Lin Li
Keyword(s):  
Calculation Model ◽  
Structure Design ◽  
Tunnel Lining ◽  
Statistical Characteristics ◽  
Underground Engineering ◽  
Reliability Design ◽  
Structure Reliability ◽  
Mechanics Model ◽  
Reliability Calculation ◽  
Lining Structure

The article proposed the reliability calculation method for tunnel lining design combining Rock-Mechanics model and Monte Carlo finite element method.The reliability calculation model of tunnel lining structure design was established considering tunnel character. The types of the statistical characteristics and distribution of axial force for the big cross section of the loess tunnel structure had been summarized. The study result stated that the method is feasible. It has important theoretical guiding significance to the practice structure reliability design of tunnel and underground engineering.

Comparative Study on Calculation Model of Hydraulic Tunnel Lining Structure between Beam Element and Solid Element

2013 ◽  
Vol 405-408 ◽  
pp. 1340-1345
Author(s):  
Jing Jing Zhang ◽  
Jun Deng ◽  
Kai Zhang ◽  
Cheng Huang
Keyword(s):  
Internal Force ◽  
Beam Element ◽  
Calculation Model ◽  
Tunnel Lining ◽  
Practical Calculation ◽  
Solid Element ◽  
Beam Analysis ◽  
Lining Structure ◽  
Calculation Results ◽  
The Right

According to the standard Specification for Design of Hydraulic Tunnels (DL/T 5195-2004), the free-flow tunnel lining structure should be calculated with beam element of finite element method that based on structural mechanics. However, the practical calculation shows that when the lining structure reaches a certain thickness, the beam element calculation results are no longer accurate. Combining with the engineering example, stress and internal force of lining structure with different thickness were calculated by using beam3 beam element and the solid65 element respectively in frame beam analysis. Differences analysis shows that the solid element is better than beam element in calculation. The influence of solid elements grid size on the result accuracy was conducted, and used to amend the calculation result of the solid element, which provides a certain reference on choosing the right element in the similar projects or structure simulation.

scholarly journals Analysis of Structural Response of Subway Shield Tunnel Lining under the Influence of Cavities

2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
Yufeng Shi ◽  
Zhaoyang Chen ◽  
Duqiang Wei ◽  
Tao Zhang ◽  
Xuming Zhou ◽  
...  
Keyword(s):  
Structural Response ◽  
Bending Moment ◽  
Tunnel Lining ◽  
Structural Safety ◽  
Shield Tunnel ◽  
Cavity Depth ◽  
Stiffness Reduction ◽  
Lining Structure ◽  
Reduction Effect ◽  
Single Cavity

The existence of cavities behind the shield tunnel lining can cause cracking, broken pieces, water leakage, and other problems, which reduces the durability and safety of the shield tunnel segment structure. In order to clarify the mechanism of cavity damage, a more systematic study of the effects of cavities on the shield tunnel lining structure from the angle, depth, and the number of cavities is carried out using model tests and numerical simulations without considering the effects of the stiffness reduction effect at the tunnel segment joints and groundwater seepage in this paper. The findings show that the bending moment value and the cavity angle value are approximately linear with the increase of single cavity angle, and the bending moment at the vault arch is reversed when the angle of the cavity behind the arch is greater than 30°. With the increase of single cavity depth, the axial force and bending moment at the cavity increase, and the distribution of bending moment remains unchanged, and the bending moment tends to be stable and unchanged beyond a certain depth. With the increase of single cavity angle and depth, the structural safety coefficient of the segment decreases, and the degree of influence is angle value > depth value. The existence of multiple cavities intensifies the influence of each cavity on the segment, especially when there are cavities behind the top and bottom of the vault; the bending moment value of the top of the vault increases by 22.53% compared with that of the single cavity condition.

scholarly journals Numerical Investigation on Crack Propagation and Fatigue Life Estimation of Shield Lining under Train Vibration Load

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Long-gang Tian ◽  
Zi-ling Cheng ◽  
Zhi-qiang Hu
Keyword(s):  
Fatigue Life ◽  
Crack Propagation ◽  
Tunnel Lining ◽  
Shield Tunnel ◽  
Vibration Load ◽  
Life Estimation ◽  
Fatigue Life Estimation ◽  
Lining Structure ◽  
Train Speed ◽  
Train Vibration

Dynamic loads such as the train vibration load usually act on the shield tunnel lining in the long term, which could make the initial flaws in shield segment propagate and gradually weaken the robustness of the tunnel structure. In this paper, a three-dimensional numerical model of shield tunnel lining structure with the initial defect is built to study its dynamic reaction and fatigue crack propagation under the train vibration load. Furthermore, the damage to intact shield segment caused by train vibration load is studied by employing the rain-flow counting method and the Miner damage theory, and a rational fatigue life estimation for the concrete shield tunnel lining is finally made. Results show that crack propagation is influenced by both the train speed and train axle, the higher the train speed, the longer the final crack, and train axle has a larger influence than train speed on the crack propagation in shield tunnel segment. The shield tunnel lining structure of Nanjing Metro Line 5 can meet the demand of working for a hundred years under the current working conditions.

Transverse Response of Underwater Shield Tunnel to Incident P Waves

2011 ◽  
Vol 90-93 ◽  
pp. 1602-1609
Author(s):  
Hong Wei Ma ◽  
Wen Hua Chen
Keyword(s):  
Seismic Response ◽  
Water Depth ◽  
Exact Analytical Solution ◽  
Incident Angle ◽  
Expansion Method ◽  
Tunnel Lining ◽  
Shield Tunnel ◽  
P Waves ◽  
Lining Structure ◽  
Underwater Tunnel

In this paper, the seismic response of underwater shield tunnel to incident P waves is investigated by using the Fourier-Bessel series expansion method. On the basis of the exact analytical solution, it is studied that the seismic response of the system which is made up of tunnel lining structure, underwater soil and water. The influence that water depth and buried depth of shield tunnel put on the seismic response of tunnel lining is given. The analytical result shows that the seismic response of tunnel lining unobvious varies with water depth change when incident P waves have a small incident angle, nevertheless, opposite conclusion appears when oblique incident P waves have a big incident angle. At a certain incident angle, the seismic response of tunnel increases with the increasing of the water depth; and the seismic response decreases with the increasing of the buried depth of underwater tunnel.

Soil-water inrush induced shield tunnel lining damage and its stabilization: A case study

2020 ◽  
Vol 97 ◽  
pp. 103290 ◽  
Author(s):  
Linchong Huang ◽  
Jianjun Ma ◽  
Mingfeng Lei ◽  
Linghui Liu ◽  
Yuexiang Lin ◽  
...  
Keyword(s):  
Soil Water ◽  
Water Inrush ◽  
Tunnel Lining ◽  
Shield Tunnel
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