scholarly journals Numerical Investigation on Dynamic Performance of a Bridge-Tunnel Transition Section with a Deep Buried Pile-Plank Structure

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Shuanglong Li ◽  
Limin Wei ◽  
Xiaobin Chen ◽  
Qun He
Keyword(s):  
Transition Zone ◽  
High Speed ◽  
Dynamic Responses ◽  
Mountainous Area ◽  
Constant Length ◽  
Transition Section ◽  
Tunnel Transition ◽  
Track Stiffness ◽  
Varying Length ◽  
Common Transition

To address the track irregularity at transition zones between subgrade and rigid structures (bridge, tunnel, etc.), some common transition approaches, such as trapezoid subgrade, were adopted in many engineering areas. However, in regard to a mountainous area, the common transition approaches may not be practicable anymore due to the limitation of the length between subgrade and rigid structures. In this paper, a new type of bridge-tunnel transition section with a deeply buried pile-plank structure (DBPPS) for short-distance transition is introduced. A three-dimensional finite element model that considers vehicle-track-subgrade coupling vibration is proposed to study the dynamic performances of a DBPPS transition section in the Shanghai–Kunming high-speed railway. With this model that has been validated with measured responses from field tests, the dynamic responses and the smoothness in track stiffness along the transition zone are analyzed. In addition, the influences of train speed, axle load, and train direction on dynamic responses are investigated, and the influences of two optimization strategies, including varying-length piles and constant-length piles, on the stiffness smoothness of the DBPPS transition section are discussed. Results show that the vibration level of the DBPPS transition section is lower than that of the abutment and the tunnel, and the additional load caused by vertical track stiffness difference aggravates the vibration at the connections between the DBPPS transition section and the abutment (or tunnel). Furthermore, the smoothness in stiffness along the transition zone can be significantly improved by the improvement strategy with varying-length piles.

Dynamic responses of bridge-approach embankment transition section of high-speed rail

2013 ◽  
Vol 20 (10) ◽  
pp. 2830-2839 ◽  
Author(s):  
Chang-wei Yang ◽  
Hai-ling Sun ◽  
Jian-jing Zhang ◽  
Chuan-bin Zhu ◽  
Li-ping Yan
Keyword(s):  
High Speed ◽  
Dynamic Responses ◽  
High Speed Rail ◽  
Transition Section ◽  
Bridge Approach

Dynamic responses of high-speed railway transition zone with various subgrade fillings

2019 ◽  
Vol 108 ◽  
pp. 17-26 ◽  
Author(s):  
Ping Hu ◽  
Chunshun Zhang ◽  
Sen Wen ◽  
Yonghe Wang
Keyword(s):  
Transition Zone ◽  
High Speed ◽  
Dynamic Responses ◽  
High Speed Railway

scholarly journals Research on Injection-Production Capability and Seepage Characteristics of Multi-Cycle Operation of Underground Gas Storage in Gas Field—Case Study of the Wen 23 Gas Storage

Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3829
Author(s):  
Jie Zhang ◽  
Feifei Fang ◽  
Wei Lin ◽  
Shusheng Gao ◽  
Yalong Li ◽  
...  
Keyword(s):  
Transition Zone ◽  
Pore Volume ◽  
High Speed ◽  
Gas Storage ◽  
Production Flow ◽  
Underground Gas Storage ◽  
Gas Recovery ◽  
Gas Drive ◽  
Gas Fields ◽  
Water Gas

With the increasing energy demands of current modern society, underground gas storage (UGS) in gas fields is the most popular type of UGS used to meet the seasonal variation of gas consumption. However, compared with gas fields, UGS in gas fields has the characteristics of periodic high-speed injection and production of exploitation modes and operation rules, which causes the rules of gas-water seepage and utilization of reserves to be more particular and complicated. In this paper, based on Wen 23 gas storage, the rules of multicycle injection and production flow and the utilization of UGS pore volume were investigated. The experimental results showed that variation in porosity and permeability caused by injection and production pressure changes in Wen 23 gas storage can be neglected. The pore volume of gas storage and the degree of gas recovery increased gradually in the pre-UGS gas zone, which was higher than that of reservoirs. In the initial stage of UGS operation, the pore volume of gas storage and the degree of gas recovery were low in the gas-drive-water gas zone as a result of water invasion during the process of reservoir exploitation. During operation of multicycle high-speed injection and production, the seepage conditions in the gas-drive-water gas zone gradually improved. The higher the reservoir permeability, the greater increases in pore volume and degree of gas recovery. In the gas-water transition zone, gas and water were reciprocated and displaced with the multicycle injection-production of UGS, resulting in the gradual deterioration of pore volume and gas recovery, which remained stable at a low value. The negative effects of reservoir heterogeneity on the effective utilization of UGS occurred in the gas-water transition zone. These findings may contribute to a better understanding of the rules of multicycle injection and production flow and utilization of UGS to optimize the injection-production efficiency of Wen 23 gas storage.

scholarly journals Analysis study the used of Tuned Mass Damper (TMD) on an existing train bridge due to high speed train with moving mass load approach

2019 ◽  
Vol 258 ◽  
pp. 05005 ◽  
Author(s):  
Wivia Octarena Nugroho ◽  
Dina Rubiana Widarda ◽  
Oryza Herdha Dwyana
Keyword(s):  
High Speed ◽  
Tuned Mass Damper ◽  
Dynamic Responses ◽  
Mass Ratio ◽  
High Speed Train ◽  
Maximum Deformation ◽  
Mass Load ◽  
Mass Damper ◽  
Existing Bridges ◽  
Comfort Criteria

As the need of the train speed increased, the existing bridges need to be evaluated, especially in dynamic responses, which are deformation and acceleration. In this study, Cisomang Bridge is modeled and analyzed due to the high-speed train SJ X2 in varying speeds, 50 km/h, 100 km/h, 150 km/h, and 200 km/h. The used of tuned mass damper also will be varied on its setting and placing. The tuned mass dampers setting be varied based on the first or second natural frequency and the placing of tuned mass damper be varied based on maximum deformation of the first or second mode. Moreover, the tuned mass damper ratio will be varied 1% and 1.6%. For all speed variations, dynamic responses of structure without TMD still fulfil the Indonesian Government Criterion based on PM 60 - 2012 but do not meet requirement of comfort criteria based on DIN-Fachbericht 101. Furthermore, only for the speed train 50km/h dynamic responses of structure fulfil safety criteria based on Eurocode EN 1990:2002, whereas the other speed variations do not meet that requirement. In the use of TMD 1% mass ratio, the structure fulfils the safety criteria for all speed variations. In the use of TMD 1.6% mass ratio, all the structure fulfils the safety and comfort criteria except 100 km/h speed which only fulfils the safety criteria.

Effect of links deformation on motion precision of parallel manipulator based on flexible dynamics

2017 ◽  
Vol 44 (6) ◽  
pp. 776-787 ◽  
Author(s):  
Chunxia Zhu ◽  
Jay Katupitiya ◽  
Jing Wang
Keyword(s):  
Parallel Manipulator ◽  
High Speed ◽  
Beam Theory ◽  
Parallel Manipulators ◽  
Dynamic Responses ◽  
Axial Deformation ◽  
Content Type ◽  
High Performing ◽  
Coupling Equations ◽  
The Relationship

Purpose Manipulator motion accuracy is a fundamental requirement for precision manufacturing equipment. Light weight manipulators in high speed motions are vulnerable to deformations. The purpose of this work is to analyze the effect of link deformation on the motion precision of parallel manipulators. Design/methodology/approach The flexible dynamics model of the links is first established by applying the Euler–Bernoulli beam theory and the assumed modal method. The rigid-flexible coupling equations of the parallel mechanism are further derived by using the Lagrange multiplier approach. The elastic energy resulting from spiral motion and link deformations are computed and analyzed. Motion errors of the 3-link torque-prismatic-torque parallel manipulator are then evaluated based on its inverse kinematics. The validation experiments are also conducted to verify the numerical results. Findings The lateral deformation and axial deformation are largest at the middle of the driven links. The axial deformation at the middle of the driven link is approximately one-tenth of the transversal deformation. However, the elastic potential energy of the transversal deformation is much smaller than the elastic force generated from axial deformation. Practical implications Knowledge on the relationship between link deformation and motion precision is useful in the design of parallel manipulators for high performing dynamic responses. Originality/value This work establishes the relationship between motion precision and the amount of link deformation in parallel manipulators.

Estimation of Track Irregularity Based on Genetic Algorithm and Unscented Kalman Filtering

2012 ◽  
Author(s):  
Hongmei Shi ◽  
Zujun Yu
Keyword(s):  
Genetic Algorithm ◽  
Kalman Filtering ◽  
High Speed ◽  
Measurement Data ◽  
Estimation Method ◽  
Coupling Model ◽  
Dynamic Responses ◽  
The Real ◽  
True Value ◽  
Track Irregularity

Track irregularity is the main excitation source of wheel-track interaction. Due to the difference of speed, axle load and suspension parameters between track inspection train and the operating trains, the data acquired from the inspection car cannot completely reflect the real status of track irregularity when the operating trains go through the rail. In this paper, an estimation method of track irregularity is proposed using genetic algorithm and Unscented Kalman Filtering. Firstly, a vehicle-track vertical coupling model is established, in which the high-speed vehicle is assumed as a rigid body with two layers of spring and damping system and the track is viewed as an elastic system with three layers. Then, the static track irregularity is estimated by genetic algorithm using the vibration data of vehicle and dynamic track irregularity which are acquired from the inspection car. And the dynamic responses of vehicle and track can be solved if the static track irregularity is known. So combining with vehicle track coupling model of different operating train, the potential dynamic track irregularity is solved by simulation, which the operating train could goes through. To get a better estimation result, Unscented Kalman Filtering (UKF) algorithm is employed to optimize the dynamic responses of rail using measurement data of vehicle vibration. The simulation results show that the estimated static track irregularity and the vibration responses of vehicle track system can go well with the true value. It can be realized to estimate the real rail status when different trains go through the rail by this method.

Typical Portal Structure for Single Track High Speed Railway Tunnel in Rugged Mountainous Area with High and Abrupt Slope

2014 ◽  
Vol 716-717 ◽  
pp. 342-346
Author(s):  
Xiao Jun Zhou ◽  
Bo Jiang ◽  
Yue Feng Zhou ◽  
Yu Yu
Keyword(s):  
High Speed ◽  
Southwest China ◽  
Earth Pressure ◽  
Mountainous Area ◽  
Single Track ◽  
Railway Tunnel ◽  
High Speed Railway ◽  
Railway Line ◽  
Bridge Abutment

On the basis of different landform and multifarious topography in rugged mountainous area in southwest China, typical tunnel portals for single track tunnels in a new high speed railway line have been presented in the paper. The portal comprises headwall, shed tunnel, bridge abutment and its support. Portal with headwall is suitable for tunnel to resist front earth pressure on high and abrupt slope. Shed tunnel is placed in front of headwall so as to prevent rockfall; its outward part is built into a flared one. Meanwhile, the installation of bridge and its abutment are also included in the portal according to landform in the paper.

The study on crossover layouts of multi-layer winding grooves in deep mine hoists based on transverse vibration characteristics of catenary rope

2018 ◽  
Vol 233 (2) ◽  
pp. 118-132
Author(s):  
Xia Peng ◽  
Xian-Sheng Gong ◽  
Jin-Jun Liu
Keyword(s):  
High Speed ◽  
Wire Rope ◽  
Processing Method ◽  
Dynamic Responses ◽  
Deep Mine ◽  
Experimental Platform ◽  
Type Selection ◽  
Lateral Oscillation ◽  
Hoisting System ◽  
Reliable Basis

In a deep mine winding hoist system, the lateral oscillation of the catenary rope is an important evaluation index of orderly rope arrangement and engineering safety. Different boundary excitations will appear when the wire rope winds on symmetrical or asymmetrical grooves, which results in the different dynamic responses of the hoisting system. In this article, the vibration equations of a deep mine hoisting system are established by using the Hamilton principle, and excitation functions of different crossover zone layouts are deduced. The operation curves are introduced to conduct the experiment based on a certain experimental platform. The lateral oscillation of the catenary rope is recorded by high-speed cameras, and an effective image processing method is proposed to obtain the vibration response of a certain point in the catenary rope. The numerical simulations are compared with the experimental results to prove the vibration models derived in this article are valid. The models could provide reliable basis for the grooves type selection in deep mine hoisting.

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