scholarly journals The Influence Evaluation of the Waste Slag Above Tunnel on the Safety of the Structure of the High-Speed Railway Tunnel

2020 ◽  
Author(s):  
Weigong Ma ◽  
Weibo He
Keyword(s):  
High Speed ◽  
Great Influence ◽  
Back Analysis ◽  
Tunnel Lining ◽  
Tunnel Structure ◽  
Destructive Testing ◽  
High Speed Railway ◽  
Lining Structure ◽  
Design Documents ◽  
The Stability

A high-speed railway loess tunnel being built is in the Shallow-Buried Section because the construction party violates the design, and the slag discarded at the top of the tunnel is just down-pressing the main line. In order to ensure that the stability of tunnel structure does not affect the safe operation in the later period, a stratum structure model is established based on non-destructive testing and on-site tunnel monitoring measurement. The parameters of surrounding rock are determined by displacement back analysis method, and the influence of waste slag on the safety of tunnel structure is checked by the parameters obtained from back analysis. Through the comparative analysis of the stress of tunnel lining under two working conditions, combined with relevant codes and design documents, it is considered that the slag has a great influence on the stress of tunnel lining structure, but the sectional strength and maximum crack width of eccentrically compressed components of tunnel lining meet the design requirements, and the structure is within the safety range.

Dynamic Performance of High-Speed Electric Multiple Unit within Multi-Body System Simulation

2019 ◽  
Vol 12 (4) ◽  
pp. 339-349
Author(s):  
Junguo Wang ◽  
Daoping Gong ◽  
Rui Sun ◽  
Yongxiang Zhao
Keyword(s):  
High Speed ◽  
Rapid Development ◽  
Dynamic Performance ◽  
Body System ◽  
High Speed Railway ◽  
Evaluation Indexes ◽  
Actual Operation ◽  
Multiple Unit ◽  
The Stability ◽  
Multi Body

Background: With the rapid development of the high-speed railway, the dynamic performance such as running stability and safety of the high-speed train is increasingly important. This paper focuses on the dynamic performance of high-speed Electric Multiple Unit (EMU), especially the dynamic characteristics of the bogie frame and car body. Various patents have been discussed in this article. Objective: To develop the Multi-Body System (MBS) model of EMU, verify whether the dynamic performance meets the actual operation requirements, and provide some useful information for dynamics and structural design of the proposed EMU. Methods: According to the technical characteristics of a typical EMU, a MBS model is established via SIMPACK, and the measured data of China high-speed railway is taken as the excitation of track random irregularity. To test the dynamic performance of the EMU, including the stability and safety, some evaluation indexes such as wheel-axle lateral forces, wheel-axle lateral vertical forces, derailment coefficients and wheel unloading rates are also calculated and analyzed in detail. Results: The MBS model of EMU has better dynamic performance especially curving performance, and some evaluation indexes of the stability and safety have also reached China’s high-speed railway standards. Conclusion: The effectiveness of the proposed MBS model is verified, and the dynamic performance of the MBS model can meet the design requirements of high-speed EMU.

scholarly journals Fatigue Life Characteristics of Segmental Lining Structure for the Shallow Buried Metro Tunnel under the Dynamic Load of a High-Speed Railway

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Wangping Qian ◽  
Taiyue Qi ◽  
Qing Zhao ◽  
Bingrong Pu ◽  
Jin Zhang ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Fatigue Failure ◽  
Dynamic Load ◽  
High Speed ◽  
Dynamic Loads ◽  
High Speed Railway ◽  
Segmental Lining ◽  
Lining Structure ◽  
Metro Tunnel

Shallow buried shield metro tunnels constructed underneath subgrade project of high-speed railways are becoming increasingly common in China, but the lower metro tunnel bears the fatigue effect of dynamic load induced by the upper high-speed railway, so the long-term durability of segmental lining is a nonnegligible problem. The segmental lining structure of metro tunnel is in a state of static-dynamic loads for a long time, especially when a high-speed railway passes above the metro line, and the long-term durability of segmental lining needs further research. Based on theoretical analysis, the effect of different forms of loads on the fatigue life was analyzed, the change law of the static-dynamic loads on segmental lining was summarized, and the method was put forward to evaluate the fatigue life characteristics of segmental lining. The research results reveal that the additional dynamic load is the fundamental reason for the fatigue failure of the structure, and the existence of static load can cause and accelerate the occurrence of structural fatigue failure simultaneously. The results indicate that the fatigue life decreases gradually with the increase of static-dynamic load. Based on coupling analysis of static-dynamic loads of segmental lining, the fatigue life increases first and then decreases with the increase of buried depth of metro tunnel, and it remains unchanged when the depth exceeds a certain value. According to the actual metro tunnel engineering, by using ABAQUS software, a three-dimensional numerical simulation was carried out to analyze the characteristics of the fatigue life and evolution rules of segmental lining. Based on the modified fatigue life formula and metro service life, the optimization design of the buried depth was carried out to determine the most reasonable range of the buried depth. This study provides a valuable reference for safe operation and long-term durability of metro tunnels under high-speed railways.

Design of High Speed Railway Tunnel and its Construction Method in Abrupt Slope with Loose Rockmass

2014 ◽  
Vol 580-583 ◽  
pp. 1096-1099 ◽  
Author(s):  
Xiao Jun Zhou ◽  
Bo Jiang ◽  
Rui Yang ◽  
Chao Ning
Keyword(s):  
High Speed ◽  
Rational Design ◽  
Composite Fiber ◽  
Railway Tunnel ◽  
High Speed Railway ◽  
Working Face ◽  
Tunneling Method ◽  
Geological Conditions ◽  
The Stability ◽  
Tunnel Portal

This paper mainly deals with the structural design of high speed railway tunnel and its driving method in abrupt slope with loose rockmass, meanwhile summarizes the connection between tunnel portal and bridge abutment in loose rockmass according to complicated landform and geology. The anti-slide piles are adopted to retain the stability of abrupt slope near the tunnel portal. In order to eliminate the risk and cost in tunnel construction, four bench cut method is invented to satisfy the safe excavation of loose rockmass in the tunnel. Composite fiber rockbolt is also employed to keep the stability of working face while driving the tunnel. The innovative tunneling method presented in the paper can be applied to guide the rational design and economical construction of high speed railway tunnels in loose surrounding rock under harsh geological conditions.

Back Analysis of Parameters and Settlement Prediction of Chengdu Clay Ground Considering Its Creep Behavior

2013 ◽  
Vol 671-674 ◽  
pp. 23-26 ◽  
Author(s):  
Yan Feng ◽  
Jian Fang Li
Keyword(s):  
High Speed ◽  
Back Analysis ◽  
Elastic Parameters ◽  
High Speed Railway ◽  
Settlement Prediction ◽  
Burgers Model ◽  
Railway Construction ◽  
Clay Ground ◽  
Railway Construction Project

Chengdu - Mianyang – Leshan (C-M-L for short) high speed railway in Chengdu section is located in the ground of weathered Mud rock overlying deep Chengdu clay area. Based on Chengdu clay ground of in high-speed railway construction project of CML, this article introduced the Burgers model to establish the objective function to analysis rheological constitutive model. The visco-elastic parameters of Burgers model are determined by back analysis of field monitoring data. By the method of iterative back analysis by layer of visco-elastic parameters, based on measured result, predicted the late settlement, and comparison with the follow-up observations records to verify the Burgers model.

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.

Development of New Type Settlement Plate in Settlement Observation on High-Speed Railway

2011 ◽  
Vol 52-54 ◽  
pp. 529-532
Author(s):  
Huai Ping Feng ◽  
Jian Mei Chang ◽  
Zu Run Yue
Keyword(s):  
High Speed ◽  
High Accuracy ◽  
High Speed Railway ◽  
Type Settlement ◽  
Settlement Plate ◽  
New Type ◽  
The Stability ◽  
Passenger Dedicated Line

The stability and smoothness of embankment is very important factors for the design of a new high-speed railway project. To make an accuracy prediction of the post-construction settlement, it is necessary to carry out a carefully settlement observation during the construction of embankment. The defects of traditional settlement plate, however, are well known as disturbing construction and destroyed easily by construction. In this paper, based on the application in Shi-Wu passenger dedicated line, a new type of settlement plate has been developed. The application of this new type of settlement plate in site shows that it has no any disturbs on the pavement and compaction of embankment. And measurement becomes simple and easy to operation. Accordingly, high accuracy of settlement observation can be obtained by this method, which has the value of application in high-speed railway settlement observation.

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