scholarly journals Application of Hyperstatic Reaction Method for Designing of Tunnel Permanent Lining, Part II: 3D Numerical Modelling

2016 ◽  
Vol 2 (6) ◽  
pp. 254-261
Author(s):  
Rahim Hassani ◽  
Rouhollah Basirat
Keyword(s):  
Numerical Modelling ◽  
Dimensional Analysis ◽  
Three Dimensional ◽  
Bending Moment ◽  
Tunnel Lining ◽  
Reaction Method ◽  
Axial Forces ◽  
Road Tunnels ◽  
Design Earthquake ◽  
Hyperstatic Reaction Method

Underground structures often have abrupt changes in structural stiffness or ground conditions such as junctions of tunnels, tunnel portal in slopes, and niches in road tunnels. At these locations, stiffness differences may subject the structure to differential movements and generate stress concentrations. Because of adversity in these issues, they need a three dimensional analysis. This paper proposes a numerical approach to the hyperstatic reaction method (HRM) for three dimensional analysis of permanent tunnel linings. In this paper, three dimensional numerical modelling is performed by considering hyperstatic reaction concepts. Designing is done for Manjil-Rudabar freeway project, Tunnel No. 2. The numerical analyses performed for Operational Design Earthquake (ODE) and Maximum Design Earthquake (MDE) loading conditions. Then interaction diagram between axial force and bending moment used for investigating the capacity of tunnel lining. The numerical results show that although more axial forces are created in tunnel lining for ODE condition, but the points in the P-M diagrams are located in the furthest distance to the diagram border (tunnel supporting system); because of less bending moment in this condition. Therefore, the safety factor in ODE condition is more than MDE condition. This numerical processing presented that the HRM is a proper, fast, and practical method for tunnel designers.

scholarly journals Application of Hyperstatic Reaction Method for Designing of Tunnel Permanent Lining, Part I: 2D Numerical Modelling

2016 ◽  
Vol 2 (6) ◽  
pp. 244-253 ◽  
Author(s):  
Rahim Hassani ◽  
Rouhollah Basirat
Keyword(s):  
Numerical Modelling ◽  
Bending Moment ◽  
Practical Method ◽  
Tunnel Lining ◽  
Earthquake Loading ◽  
Reaction Method ◽  
Simplified Approach ◽  
Design Earthquake ◽  
Hyperstatic Reaction Method

The increase of bored tunnels in the entire world has raised the question how to design the tunnel structure in an efficient way. This paper proposes a numerical approach to the Hyperstatic Reaction Method (HRM) for analysing permanent tunnel linings. The permanent tunnel lining is known as main structure of tunnel maintenance during the time. The HRM is one of the analysis methods for tunnel lining in long term. In this paper, two dimensional numerical modelling is performed by considering hyperstatic reaction concepts. Loading is done after the calculation of long term loads, and ground reaction is simulated by springs. Designing is done for Manjil-Rudabar freeway project, Tunnel No. 2. The numerical analyses were performed for Operational Design Earthquake (ODE) and Maximum Design Earthquake (MDE) loading conditions. A new simplified approach is used for considering the effect of earthquake loading on the tunnel lining. Then, an interaction diagram between axial force and bending moment used for investigating the capacity of tunnel lining. The thickness of tunnel lining and armature are calculated for three sections based on induced forces in tunnel lining. These forces were different in every section according to the load combinations, rock mechanics properties, lining properties, and overburden.  The numerical results showed that the forces in tunnel lining for MDE condition is approximately 50% more than ODE condition in earthquake loading. This numerical processing presented that the HRM is a proper, fast, and practical method for designing and analysing the tunnel lining.

Three-dimensional numerical modelling of shield tunnel lining

2006 ◽  
Vol 21 (3-4) ◽  
pp. 434 ◽  
Author(s):  
Zheng-rong Huang ◽  
Wei Zhu ◽  
Jing-hua Liang ◽  
Jian Lin ◽  
Rui Jia
Keyword(s):  
Numerical Modelling ◽  
Three Dimensional ◽  
Tunnel Lining ◽  
Shield Tunnel

Coupled Numerical Analysis of Tunnel Excavation in Saturated Soft Clay under High Groundwater

2011 ◽  
Vol 368-373 ◽  
pp. 2533-2536
Author(s):  
Hua Yuan ◽  
Hai Tao Wan ◽  
Zhi Liang Zhao
Keyword(s):  
Soft Clay ◽  
Three Dimensional ◽  
Bending Moment ◽  
High Water ◽  
Shield Tunnel ◽  
Deep Soil ◽  
Tunnel Excavation ◽  
Axial Forces ◽  
Reduction Effect ◽  
Saturated Soft Clay

A coupled numerical simulation of a river-crossing shield tunnel excavation in saturated soft clay with high groundwater has been performed using a three-dimensional finite difference model, which takes into account variation of soil permeability with stress, anisotropy of permeability, reduction effect of joints on segment bending stiffness and the hardening process of synchronized grouting material. Groundwater seepage conditions around the tunnel, bending moment, axial forces and strength safety factor of tunnel segment as well as deep soil displacement during tunnel diving are investigated numerically. The analyses provide valuable information concerning the mechanical behavior of tunnel segment and hydrological field in soil around tunnel during advancing. The result also is benefited to control groundwater for river-crossing tunnel in soft clay under high water table.

Reliability of tunnel lining design using the Hyperstatic Reaction Method

2018 ◽  
Vol 77 ◽  
pp. 59-67 ◽  
Author(s):  
Henrique M. Kroetz ◽  
Ngoc Anh Do ◽  
Daniel Dias ◽  
André T. Beck
Keyword(s):  
Tunnel Lining ◽  
Reaction Method ◽  
Tunnel Lining Design ◽  
Hyperstatic Reaction Method

scholarly journals U-shaped tunnel lining design using the Hyperstatic Reaction Method – Influence of the invert

2020 ◽  
Vol 60 (3) ◽  
pp. 592-607
Author(s):  
Dianchun Du ◽  
Daniel Dias ◽  
Ngocanh Do ◽  
Tronghung Vo
Keyword(s):  
Tunnel Lining ◽  
Reaction Method ◽  
Tunnel Lining Design ◽  
Hyperstatic Reaction Method

scholarly journals Use of tire-derived aggregate in tunnel cut-and-cover

2018 ◽  
Vol 55 (7) ◽  
pp. 968-978 ◽  
Author(s):  
Luis Medina Rodríguez ◽  
Marcos Arroyo ◽  
Miguel Martín Cano
Keyword(s):  
Constitutive Model ◽  
Case History ◽  
Three Dimensional ◽  
Bending Moment ◽  
Tunnel Lining ◽  
Numerical Analyses ◽  
Railway Tunnel ◽  
Tunnel Section ◽  
Tire Derived Aggregate

A case history is reported in which tire-derived aggregate (TDA) was successfully applied to reduce the weight of fill upon a cut-and-cover railway tunnel. Subsequent three-dimensional numerical analyses are used to explore the effect of different assumptions about the constitutive model of the TDA material. Alternative dispositions of TDA around the tunnel section are also examined. Reductions of up to 60% in lining bending moment may be achieved. For the case analyzed, the elastic description of the TDA has little influence on tunnel lining loads, although it is important for fill settlement estimates.

scholarly journals Neck Vertebral Level-specific Forces and Moments Under G-x Accelerative Loading

2021 ◽  
Vol 186 (Supplement_1) ◽  
pp. 625-631
Author(s):  
Yuvaraj Purushothaman ◽  
John Humm ◽  
Davidson Jebaseelan ◽  
Narayan Yoganandan
Keyword(s):  
Three Dimensional ◽  
Spinal Column ◽  
Bending Moment ◽  
Element Model ◽  
Whole Body ◽  
Shear Forces ◽  
Male And Female ◽  
Axial Forces ◽  
Impact Acceleration ◽  
Three Dimensional Finite Element

ABSTRACT Introduction It is important to determine the local forces and moments across the entire cervical spine as dysfunctions such as spondylosis and acceleration-induced injuries are focused on specific levels/segments. The aims of the study were to determine the axial and shear forces and moments at each level under G-x accelerative loading for female and male spines. Methods A three-dimensional finite element model of the male head-cervical spinal column was developed. G-x impact acceleration was applied using experimental data from whole body human cadaver tests. It was validated with experimental head kinematics. The model was converted to a female model, and the same input was applied. Segmental axial and shear forces and moments were obtained at all levels from C2 to T1 in male and female spines. Results The time of occurrence of peak axial forces in male and female spines ranged from 37 to 41 ms and 31 to 35 ms. The peak times for the shear forces in male and female spines ranged from 65 to 86 ms and 58 to 78 ms. The peak times for the bending moment ranged from 79 to 91 ms for male and 75 to 83 ms for female spines. Other data are given. Conclusions All metrics reached their peaks earlier in female than male spines, representing a quicker loading in the female spine. Peak magnitudes were also lower in the female spines. Moments and axial forces varied differently compared to the shear forces in the female spine, suggesting that intersegmental loads vary nonuniformly. Effects of head inertia contributed to the greatest increase in axial force under this impact acceleration vector. Because female spines have a lower biomechanical tolerance to injury, female spines may be more vulnerable to injury under this load vector.

In situ investigation of the primary recrystallization of alpha titanium in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 634-635
Author(s):  
S. Naka ◽  
R. Penelle ◽  
R. Valle
Keyword(s):  
Dimensional Analysis ◽  
Texture Evolution ◽  
Cold Work ◽  
Three Dimensional ◽  
Primary Recrystallization ◽  
Thin Foils ◽  
In Situ Investigation ◽  
Grain Growth Model ◽  
Alpha Titanium

The in situ experimentation technique in HVEM seems to be particularly suitable to clarify the processes involved in recrystallization. The material under investigation was unidirectionally cold-rolled titanium of commercial purity. The problem was approached in two different ways. The three-dimensional analysis of textures was used to describe the texture evolution during the primary recrystallization. Observations of bulk-annealed specimens or thin foils annealed in the microscope were also made in order to provide information concerning the mechanisms involved in the formation of new grains. In contrast to the already published work on titanium, this investigation takes into consideration different values of the cold-work ratio, the temperature and the annealing time.Two different models are commonly used to explain the recrystallization textures i.e. the selective grain growth model (Beck) or the oriented nucleation model (Burgers). The three-dimensional analysis of both the rolling and recrystallization textures was performed to identify the mechanismsl involved in the recrystallization of titanium.

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