Numerical Analysis of Initial Support and Secondary Lining Contact Pressure of Phyllite Tunnel

2014 ◽  
Vol 884-885 ◽  
pp. 675-678
Author(s):  
Xin Zhe Li ◽  
Geng Feng Wang ◽  
Xin Liang Li ◽  
Zhong Rong Zhu
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Contact Pressure ◽  
Surrounding Rock ◽  
Before And After ◽  
Initial Support ◽  
Secondary Lining

Taking Jin Chuan phyllite tunnel as the research object, and based on numerical simulation of surrounding rock graded III, IV and V, the paper studied the stress characteristics of initial support and four other representative locations such as two arch vault, arch spandrel, arch haunch, and arch foot during and after the process of construction. The paper focuses on the stress characteristics of secondary lining in different locations after stability and the change of stress in different locations of initial lining before and after the secondary lining construction.

Numerical Analysis for Bolt Length Based on the Stress Response of Anchorage Surrounding Rock

2012 ◽  
Vol 204-208 ◽  
pp. 4481-4485
Author(s):  
Bin Wang ◽  
Fu Jun Zhao ◽  
Wen Bin Peng
Keyword(s):  
Numerical Simulation ◽  
Stress Response ◽  
Numerical Analysis ◽  
Bearing Capacity ◽  
Distribution Curve ◽  
Surrounding Rock ◽  
Effective Length ◽  
Plastic Failure ◽  
Deep Rock ◽  
Peak Value

The current researches on bolt length are rarely concerned with self-bearing characteristics of anchorage surrounding rock，its stress response is seldom used to analyze the bolt effective length. Tangential stress σθ of surrounding rock is sensitive to mechanical variation of surrounding rock plastic failure fields. When surrounding rock bolted, the distribution curve of σθ presents internal and external peak values from the surface rock to the deep rock, which is verified by numerical simulation. Internal peak value of σθ curve increases with the bolt length, which means the bearing capacity of surrounding rock in plastic failure division is improved, correspondingly, external peak value decreases which shows the supporting behavior of the deep rock is weakened. The results of numerical simulations prove that there exists an effective value of bolt length. If bolt length beyond it, the bearing capacity of anchorage surrounding rock cannot be improved obviously.

scholarly journals Numerical analysis and application of the construction method for the small interval tunnel in the turn line of metro

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042093206 ◽  
Author(s):  
Zhanping Song ◽  
Xiaoxu Tian ◽  
Qi Liu ◽  
Yuwei Zhang ◽  
Heng Li ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Construction Method ◽  
Surface Settlement ◽  
Underground Excavation ◽  
Small Interval ◽  
Resource Configuration ◽  
Construction Methods ◽  
Initial Support ◽  
Left And Right

The surrounding rock may become unstable or even fall down and the initial support may crack and be destroyed when the construction method of the underground excavation tunnel is not properly selected in the turn line of metro. . A section of the Santunbei turn line of Urumqi Metro Line 1# was taken as the engineering background. The proposed construction method was analyzed by numerical simulation. Numerical analysis shows that the final surface settlement caused by the proposed construction method is 3.0 mm and the horizontal convergence is 3.2 mm. It also turns out that the proposed construction method causes less deformation, and the method can be applied to the construction of the small interval tunnel in the Santunbei turn line of metro. The rationality of the method and numerical model was further verified by comparison between the monitored data of surface settlement, horizontal convergence and vault sinking, and numerical simulation results. Finally, the deformation and stress of the six construction methods were compared. The deformation and stress caused by the six construction methods are almost the same. It indicates that the construction spacing between the left and right tunnels does not affect the safety of tunnel construction. Therefore, the appropriate construction spacing could be selected according to the resource configuration, instead of deformation and stress.

The Numerical Analysis on Stability of Deep Roadway Support System

2012 ◽  
Vol 193-194 ◽  
pp. 687-692
Author(s):  
Zhen Yan Xiao ◽  
Yu Liu
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Support System ◽  
Simulation Software ◽  
Surrounding Rock ◽  
Reinforcement Effect ◽  
Rock Bolts ◽  
Roadway Support

The effect of the roadway with no supporting and roadway that was reinforcement by rock bolts and anchor robs, anchor rod combined bolting shoring, anchor rod combined anchor rope and lining timbering was simulated by using numerical simulation software FLAC3D. The results showed that the deformation of no supporting roadway is maximal, and the maximal position is vault. The displacement of top floor and two side decreases after supported, which can reinforce surrounding rock. The reinforcement effect of the anchor rod combined anchor rope and lining timbering is best.

Numerical Analysis of Damage for Y-Shape Tunnel

2011 ◽  
Vol 368-373 ◽  
pp. 2517-2520
Author(s):  
Da Ming Lin ◽  
Yan Jun Shang ◽  
Guo He Li ◽  
Yuan Chun Sun
Keyword(s):  
Numerical Simulation ◽  
Rock Mass ◽  
Numerical Analysis ◽  
Plastic Zone ◽  
Comprehensive Analysis ◽  
Surrounding Rock ◽  
Tunnel Construction ◽  
Deformation And Failure ◽  
Single Beam ◽  
Flac 3D

There are many effective researches about tunnel at home and abroad, because the complexity of design and construction for Y-shape tunnel, in public there is no research about it yet, with the background of nanliang-tunnel which merge two single-beam into a two-lane tunnel as Y-shape. This paper obtains the rock mass mechanics parameters on the basis of nonlinear Hoek-Brown criterion first, and has a numerical simulation according the tunnel construction with FLAC-3D. we arrange many monitor sections in this model and discuss the law of deformation and failure in different section, at last have a comprehensive analysis of displacement, stress, plastic zone of different sites which caused by tunnel construction and discover that: with the distance of two single tunnels decreased, the interaction caused by the merging increase together with the compressive stress, tensile stress. The displacements of surrounding rock increase corresponding, the amplitude of variation is up to 44.8%, After the two-lane tunnel is 15m long, the stress and displacements redistribution of surrounding rock become stable.

scholarly journals Deformation Mechanism and Control Technology of the Surrounding Rock of the Floor Roadway under the Influence of Mining

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Qingchong Zhao ◽  
Baojie Fu ◽  
Jiadi Yin
Keyword(s):  
Numerical Simulation ◽  
Surface Displacement ◽  
Surrounding Rock ◽  
Infinite Body ◽  
Maximum Displacement ◽  
Deformation And Failure ◽  
Working Face ◽  
Before And After ◽  
Stress And Deformation ◽  
Two Sides

Deformation and failure mechanism of the surrounding rock of the floor roadway under the influence of working face mining is complicated, and roadway control is difficult. The floor roadway of the 11123 working face in Pan’er Mine is taken as the research object of this study based on semi-infinite body theory of elastic mechanics to establish a mechanical model along the advancing direction of the working face and derive the stress expression of any point in the affected area of floor mining. According to the theoretical results, effective reinforcement and support schemes are then proposed. FLAC3D numerical simulation analyzes the stress and deformation of the surrounding rock of the floor roadway before and after the reinforcement. The numerical simulation results showed that (1) mining abutment pressure of the overlying working face forms a certain range of stress concentration on the roof and two sides of the roadway and will cause deformation and damage to the floor roadway and (2) overall bearing capacity of the surrounding rock of the roadway is significantly improved, and surface displacement of the floor roadway is reduced by 64 mm through the reinforcement and support of the floor roadway. On-site monitoring data of the floor roadway in the 11123 working face of Pan’er Mine showed that the maximum displacement of the roadway roof and two sides is controlled at approximately 80 mm, and the surrounding rock deformation of the roadway is appropriately controlled to meet the needs of safe production.

scholarly journals Numerical analysis of landslide next regional route No. 975 in Borowa before and after securing it

2018 ◽  
Vol 19 (6) ◽  
pp. 202-206
Author(s):  
Elżbieta Pilecka ◽  
Magdalena Moskal
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Reduction Method ◽  
Strength Reduction ◽  
Strength Reduction Method ◽  
Security Measures ◽  
Road Engineering ◽  
Shear Strength Reduction Method ◽  
Before And After ◽  
Shear Strength Reduction

In the paper the problem of landslides in road engineering is discussed. An example is given of a landslide next to regional road No. 975 in Borowa. The analysed slope was modeled in the MIDAS GTS NX . The slope stability analysis and the FoS coefficient were carried out using the shear strength reduction method (SRM). In the next step a numerical analysis was carried out after the security measures were implemented. The results show the capability of numerical simulation programs.

Stability Analysis of Tunnel during the Excavation Based on ANSYS

2014 ◽  
Vol 577 ◽  
pp. 1135-1138
Author(s):  
Bing He ◽  
Guang Zhi Yin
Keyword(s):  
Numerical Simulation ◽  
Stability Analysis ◽  
Stress Condition ◽  
Stability Control ◽  
Simulation Software ◽  
Surrounding Rock ◽  
Geological Condition ◽  
Rock Stability ◽  
Before And After ◽  
The Stability

This paper combines the geological condition of Miaoziwan tunnel and numerical simulation software ANSYS to analyze the displacement and stress condition of surrounding rock before and after the excavation. Furthermore, the stability of overlying rock in the tunnel was studied based on the displacement and stress condition of surrounding rock. The breaking law of overlying rock was studied considering the influencing factors to the stability of surrounding. The study and analysis to the breaking law of overlying rock can be helpful to the improvement of surrounding rock stability control and supporting system. Moreover, the result can be the guidance to the excavation.

scholarly journals Temporal and Spatial Effect of Surrounding Rock and Supporting Construction of a Large Soil Tunnel

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Wanjun Ye ◽  
Yuntao Wu ◽  
Ming Chen ◽  
Chong Gao
Keyword(s):  
Contact Pressure ◽  
Rock Pressure ◽  
Release Rate ◽  
Rapid Growth ◽  
High Speed ◽  
Surrounding Rock ◽  
Measuring Point ◽  
Finite Element Software ◽  
Surrounding Rock Pressure ◽  
Secondary Lining

Based on the Zaosheng No. 3 tunnel of the Yinchuan-Xi’an high-speed railway, the surrounding rock pressure, contact pressure of the primary support, and secondary lining and internal force of the secondary lining concrete are systematically tested using a vibrating wire sensor, and the correlation between the advance construction distance and the surrounding rock release rate is studied with finite element software. The results show that the pressure on the surrounding rock is low when the deeply buried soil tunnel is excavated and can be divided into three stages: rapid growth, slow growth, and flattening with time. It is more reasonable to calculate the surrounding rock pressure by using tunnel planning calculations. For the contact pressure, although the value of each measuring point in the inverted arch changes a little, the arch pressure obviously has the characteristics of rapid growth and a sharp rebound. Most of the test points of the second lining concrete show a compression state, which is far less than the ultimate compressive strength. At the same time, the initial support of the tunnel bears a large load, while the secondary lining bears a relatively small force, and the load sharing ratio of the two ranges between 0.1 and 0.7; with the progress of the excavation section, the surrounding rock deformation (deformation release rate) increases gradually. When the excavation face is close to the monitoring section, the deformation (deformation release rate) is the most severe. With the increase in the distance between the excavation section and the monitoring section, the deformation (deformation release rate) tends to be flat.

Numerical Analysis of Construction Method in Shallow-Buried Large-Section Loess Tunnel

2014 ◽  
Vol 580-583 ◽  
pp. 997-1000 ◽  
Author(s):  
Zhi Jie Sun
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Ground Surface ◽  
Construction Method ◽  
Surrounding Rock ◽  
3D Numerical Simulation ◽  
Large Section ◽  
Research Results ◽  
Construction Methods ◽  
Ground Surface Settlement

To research the deformation regularity of large section loess tunnel in construction procession with different construction methods, 3D Numerical Simulation is applied and the large-section loess tunnel of highway is taken as an example. Comparing deformation regularity of surrounding rock in three types of construction method conditions, the research results show that:The CRD method takes precedence in the condition of the convergence of surrounding rock is large. The both sides heading method takes precedence in the condition of ground surface settlement is large.

Field Monitoring and Numerical Simulation Study on Mechanical Characteristics of Extra-Long Highway Tunnel

2012 ◽  
Vol 170-173 ◽  
pp. 1450-1454
Author(s):  
Xun Li ◽  
Chuan He ◽  
Guo Wen Xu
Keyword(s):  
Numerical Simulation ◽  
Mechanical Characteristics ◽  
Safety Monitoring ◽  
Surrounding Rock ◽  
Tunnel Face ◽  
Highway Tunnel ◽  
Surrounding Rock Pressure ◽  
Secondary Lining ◽  
Monitoring And Measurement ◽  
Monitoring Information

Taking Motianling tunnel in Chongqing as an engineering background, the monitoring and measurement scheme is proposed for the extra-long tunnel under complex condition, and the field data and the numerical simulation results is analyzed. The results indicates that, the selected cross-section reflect overall state of the Motianling tunnel, and the structure safety monitoring during operation is considered; by tunnel internal and external observation, it is found that the tunnel face in F22 fault zone may not stay stability, because the monitoring information receive feedback timely, and the supporting measures is proper, the surrounding rock stay stability when excavating; for the typical section, the surrounding rock contact pressure is greater than interlayer pressure, primary lining sustains most of the load ,and the secondary lining plays an assistant role as safety reservation; the maximum of anchor axial force and surrounding rock pressure occur at tunnel crown. By monitoring and numerical simulation, the dynamic excavation and design is realized, the Motianling tunnel is achieved safely and successfully at last.

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