scholarly journals Analysis of Longitudinal Force of Beam and Rail of Continuously Welded Rails (CWR) on Railway Bridge

2022 ◽  
Vol 2148 (1) ◽  
pp. 012065
Author(s):  
Zhiping Zeng ◽  
Ji Hu ◽  
Qiang Zeng ◽  
Zhibin Huang ◽  
Huatuo Yin ◽  
...  
Keyword(s):  
Element Model ◽  
Longitudinal Force ◽  
Relative Displacement ◽  
Railway Bridge ◽  
Simply Supported ◽  
Maximum Value ◽  
Constant Resistance ◽  
Left And Right ◽  
The Right ◽  
Track Bridge

Abstract To study the longitudinal force of CWR on viaduct, a track-bridge-pier finite element model is established. Taking a multi-span simply supported beam with a maximum span of 32.7m of an elevated CWR as an example, the additional expansion and contraction forces, displacement between rail and beam and the force of pier are calculated, and whether the rail stress meets the requirements when setting constant resistance fasteners is checked. The results show that: (1) For the left and right lines, the maximum additional expansion forces of single strand rail are both 211.13kN, and the maximum relative displacements between beam and rail are both 6.572mm. (2) The maximum value of the additional expansion and contraction forces and the relative displacement between beam and rail of the same line occur at the same position. The left line is at ZFZ29 pier and the right line is at ZFS31 pier. (3) The maximum force of pier in this section is 500.80kN, and the pier numbers are ZFZ27 and ZFS29. (4) The rail stress is less than the allowable stress of 352MPa, and the rail strength meets the requirements.

Study on the Longitudinal Horizontal Stiffness Limited Value of 20m Simply Supported Beam Pier Top of Urban Rail Transit

2014 ◽  
Vol 501-504 ◽  
pp. 1129-1135
Author(s):  
Xian Xing Dai ◽  
Ting Lin Liu ◽  
Zhen Wei Xiong ◽  
Ping Wang
Keyword(s):  
Element Model ◽  
Relative Displacement ◽  
Urban Rail Transit ◽  
Rail Transit ◽  
Simply Supported Beam ◽  
Double Line ◽  
Simply Supported ◽  
Urban Rail ◽  
Bending Mode ◽  
Common Application

Considering the common application of the 20m simply supported beam in modern urban rail transit, an integrative rail-bridge-pier finite element model is developed. The force imposed on the pier, abutment and rail are calculated in different conditions, including the bridge stretching, bending and braking. In addition, the displacement of pier top and the maximum rapid relative displacement between girder and track are also calculated. The results are shown as follows: in terms of multiple span simply supported beams, the most harmful bending mode is when the load distributes on two adjacent simply supported beams. According to the additional braking tension force, as well as the additional braking pressure and the rapid relative displacement between girder and track, the most harmful breaking mode can be confirmed respectively. In the paper, the minimum value of the longitudinal horizontal linear stiffness of 20m simply supported beam piers is 120 kN/cm (double-line).

Influences of Rail Expansion Joint on Jointless Turnout on Ballasted Continuous Beam Bridge

2011 ◽  
Vol 48-49 ◽  
pp. 611-616
Author(s):  
Rong Chen ◽  
Wang Ping ◽  
Bin Wang
Keyword(s):  
Longitudinal Force ◽  
Relative Displacement ◽  
Continuous Beam ◽  
Expansion Joint ◽  
Simply Supported ◽  
Continuous Beam Bridge ◽  
Ballasted Track ◽  
Expansion Range ◽  
Stress And Deformation ◽  
Beam Bridge

Based on turnout/bridge interaction principle and finite element method (FEM), an integrated turnout/beam/pier model of jointless turnout on ballasted track was established to analyze the influences of expansion joint on stress and deformation of the turnout. The results are concluded as follows: whether the rail expansion joint is set in front of or behind the turnout, expansion additional force of stock rail will be reduced greatly at the end of the beam; so do the expansion displacement of switch rail and nose rail, the stress of displacement restrictor and spacer block, rail break gap and the longitudinal force of one rail after the other rail broke. But when the expansion joint is set in front of the turnout, the pier’s longitudinal force of continuous beam bridge and the simply supported beam bridge (within the expansion range of the device) increase greatly. When the device is close to the turnout, longitudinal relative displacement of the stock rail to the girder also increases a lot. By comparison, it is more favorable to set the expansion joint behind the turnout, or to set the device at the both ends of the continuous beam, or to set the device at the ends of continuous beam rather than in the center of the span.

Redrawing Operation a Star Shape from Cylindrical Shape Using Experimental and FE Analysis

2020 ◽  
Vol 38 (1A) ◽  
pp. 25-32
Author(s):  
Waleed Kh. Jawad ◽  
Ali T. Ikal
Keyword(s):  
Finite Element ◽  
Effective Strain ◽  
Element Model ◽  
Cylindrical Shape ◽  
Element Analysis ◽  
Punch Force ◽  
Maximum Value ◽  
Element Simulation ◽  
Blank Sheet ◽  
The Finite Element Model

The aim of this paper is to design and fabricate a star die and a cylindrical die to produce a star shape by redrawing the cylindrical shape and comparing it to the conventional method of producing a star cup drawn from the circular blank sheet using experimental (EXP) and finite element simulation (FES). The redrawing and drawing process was done to produce a star cup with the dimension of (41.5 × 34.69mm), and (30 mm). The finite element model is performed via mechanical APDL ANSYS18.0 to modulate the redrawing and drawing operation. The results of finite element analysis were compared with the experimental results and it is found that the maximum punch force (39.12KN) recorded with the production of a star shape drawn from the circular blank sheet when comparing the punch force (32.33 KN) recorded when redrawing the cylindrical shape into a star shape. This is due to the exposure of the cup produced drawn from the blank to the highest tensile stress. The highest value of the effective stress (709MPa) and effective strain (0.751) recorded with the star shape drawn from a circular blank sheet. The maximum value of lamination (8.707%) is recorded at the cup curling (the concave area) with the first method compared to the maximum value of lamination (5.822%) recorded at the cup curling (the concave area) with the second method because of this exposure to the highest concentration of stresses. The best distribution of thickness, strains, and stresses when producing a star shape by

Comparison of the efficiency of the indexes of Pont and Korkhause with Kernott technique in patients with narrowing of maxilla

2020 ◽  
Vol 20 (3) ◽  
pp. 199-203
Author(s):  
O. I. Admakin ◽  
I. A. Solop ◽  
A. D. Oksentyuk
Keyword(s):  
Dental Treatment ◽  
Standard Analysis ◽  
Clinical Hospital ◽  
Control Models ◽  
Diagnostic Models ◽  
Left And Right ◽  
The Asymmetry ◽  
The Right ◽  
The University ◽  
Medical University

Relevance. The narrowing of the maxilla is one of the most common pathologies in orthodontics. Recent studies show that the narrowing is always asymmetric which is connected to the rotation of the maxilla. To choose the treatment correctly one need a calculation that reveals the asymmetry, which is impossible with using standard indexes.Purpose – to compare efficiency of indexes of Pont and Korkhause with the Kernott's method in patients with narrowing of the maxilla.Materials and methods. The study involved 35 children aged from 8 to 12 years old undergoing dental treatment in the University Children's Clinical Hospital of the First Moscow State Medical University with no comorbidities. For every patient a gypsum model was prepared and after that to carry out the biometrical calculation. In this study two indexes were used: Pont's index and Korkhause's; using this standard analysis the narrowing of the maxilla was revealed. After using Pont's Index and Korkhaus analysis all the models were calculated by the method of Kernott with Kernott's dynamic pentagon.Results. As a result of the analysis of the control diagnostic models a narrowing of the maxilla in 69% of cases (n = 24) was revealed in all cases, the deviation of the size of the dentition was asymmetric. Thus, 65% of the surveyed models showed a narrowing on the right. This narrowing was of a different severity and averaged 15 control models.Conclusions. This shows that for the biometrics of diagnostic models it is necessary to use methods that allow to estimate the width of the dentition rows on the left and on the right separately. To correct the asymmetric narrowing of the dentition, it is preferable to use non-classical expanding devices that act equally on the left and right sides separetly.

scholarly journals An Electrostatic Self-Excited Resonator with Pre-Tension/Pre-Compression Constraint for Active Rotation Control

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 650
Author(s):  
Ruide Yun ◽  
Yangsheng Zhu ◽  
Zhiwei Liu ◽  
Jianmei Huang ◽  
Xiaojun Yan ◽  
...  
Keyword(s):  
Maximum Velocity ◽  
Flapping Wings ◽  
Variable Velocity ◽  
Beam Length ◽  
Dc Voltage ◽  
Middle Position ◽  
Simply Supported ◽  
Maximum Value ◽  
Constraint Structure

We report a novel electrostatic self-excited resonator driven by DC voltage that achieves variable velocity-position characteristics via applying the pre-tension/pre-compression constraint. The resonator consists of a simply supported micro-beam, two plate electrodes, and two adjustable constraint bases, and it can be under pre-compression or pre-tension constraint by adjusting the distance L between two constraint bases (when beam length l > L, the resonator is under pre-compression and when l < L, it is under pre-tension). The oscillating velocity of the beam reaches the maximum value in the position around electrodes under the pre-compression constraint and reaches the maximum value in the middle position between two electrodes under the pre-tension condition. By changing the constraint of the microbeam, the position of the maximum velocity output of the oscillating beam can be controlled. The electrostatic self-excited resonator with a simple constraint structure under DC voltage has great potential in the field of propulsion of micro-robots, such as active rotation control of flapping wings.

scholarly journals Transcriptomic uniqueness and commonality of the ion channels and transporters in the four heart chambers

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sanda Iacobas ◽  
Bogdan Amuzescu ◽  
Dumitru A. Iacobas
Keyword(s):  
Ion Channels ◽  
Cycle Phase ◽  
Functional Roles ◽  
Expression Control ◽  
Gene Expression Control ◽  
Left And Right ◽  
The Right ◽  
Phase Out ◽  
Right Atria ◽  
Agilent Microarrays

AbstractMyocardium transcriptomes of left and right atria and ventricles from four adult male C57Bl/6j mice were profiled with Agilent microarrays to identify the differences responsible for the distinct functional roles of the four heart chambers. Female mice were not investigated owing to their transcriptome dependence on the estrous cycle phase. Out of the quantified 16,886 unigenes, 15.76% on the left side and 16.5% on the right side exhibited differential expression between the atrium and the ventricle, while 5.8% of genes were differently expressed between the two atria and only 1.2% between the two ventricles. The study revealed also chamber differences in gene expression control and coordination. We analyzed ion channels and transporters, and genes within the cardiac muscle contraction, oxidative phosphorylation, glycolysis/gluconeogenesis, calcium and adrenergic signaling pathways. Interestingly, while expression of Ank2 oscillates in phase with all 27 quantified binding partners in the left ventricle, the percentage of in-phase oscillating partners of Ank2 is 15% and 37% in the left and right atria and 74% in the right ventricle. The analysis indicated high interventricular synchrony of the ion channels expressions and the substantially lower synchrony between the two atria and between the atrium and the ventricle from the same side.

The role of visual experience for spatial numerical associations

2012 ◽  
Vol 25 (0) ◽  
pp. 222 ◽  
Author(s):  
Michael J. Proulx ◽  
Achille Pasqualotto ◽  
Shuichiro Taya
Keyword(s):  
Visual Experience ◽  
Opposite Effect ◽  
Random Number Generation ◽  
Number Line ◽  
Mental Number Line ◽  
Generation Task ◽  
Congenitally Blind ◽  
Left And Right ◽  
The Right

The topographic representation of space interacts with the mental representation of number. Evidence for such number–space relations have been reported in both synaesthetic and non-synaesthetic participants. Thus far most studies have only examined related effects in sighted participants. For example, the mental number line increases in magnitude from left to right in sighted individuals (Loetscher et al., 2008, Curr. Biol.). What is unclear is whether this association arises from innate mechanisms or requires visual experience early in life to develop in this way. Here we investigated the role of visual experience for the left to right spatial numerical association using a random number generation task in congenitally blind, late blind, and blindfolded sighted participants. Participants orally generated numbers randomly whilst turning their head to the left and right. Sighted participants generated smaller numbers when they turned their head to the left than to the right, consistent with past results. In contrast, congenitally blind participants generated smaller numbers when they turned their head to the right than to the left, exhibiting the opposite effect. The results of the late blind participants showed an intermediate profile between that of the sighted and congenitally blind participants. Visual experience early in life is therefore necessary for the development of the spatial numerical association of the mental number line.

Dynamic Response of the Spectral Element Model by Using the FFT

2007 ◽  
Vol 345-346 ◽  
pp. 845-848
Author(s):  
Joo Yong Cho ◽  
Han Suk Go ◽  
Usik Lee
Keyword(s):  
Fourier Transforms ◽  
Initial Conditions ◽  
Element Model ◽  
Spectral Element ◽  
Dynamic Responses ◽  
Analysis Method ◽  
Euler Beam ◽  
Exact Analytical Solutions ◽  
Simply Supported ◽  
Spectral Analysis Method

In this paper, a fast Fourier transforms (FFT)-based spectral analysis method (SAM) is proposed for the dynamic analysis of spectral element models subjected to the non-zero initial conditions. To evaluate the proposed SAM, the spectral element model for the simply supported Bernoulli-Euler beam is considered as an example problem. The accuracy of the proposed SAM is evaluated by comparing the dynamic responses obtained by SAM with the exact analytical solutions.

Case Study of the 156 m Simply Supported Steel Truss Railway Bridge

2017 ◽  
Vol 27 (4) ◽  
pp. 563-568 ◽  
Author(s):  
Xiangdong Yu ◽  
Yongle Deng ◽  
Bin Yan
Keyword(s):  
Railway Bridge ◽  
Simply Supported ◽  
Steel Truss

scholarly journals Surface Evolution During Semiconductor Processing

VLSI Design ◽  
1998 ◽  
Vol 6 (1-4) ◽  
pp. 379-384 ◽  
Author(s):  
Ganesh Rajagopalan ◽  
Vadali Mahadev ◽  
Timothy S. Cale
Keyword(s):  
Riemann Problem ◽  
Surface Profile ◽  
Numerical Implementation ◽  
Jump Conditions ◽  
Semiconductor Processing ◽  
Explicit Integration ◽  
Surface Evolution ◽  
Left And Right ◽  
The Right ◽  
Surface Angle

We discuss our approach to using the Riemann problem to compute surface profile evolution during the simulation of deposition, etch and reflow processes. Each pair of segments which represents the surface is processed sequentially. For cases in which both segments are the same material, the Riemann problem is solved. For cases in which the two segments are different materials, two Riemann problems are solved. The material boundary is treated as the right segment for the left material and as the left segment for the right material. The critical equations for the analyses are the characteristics of the Riemann problem and the ‘jump conditions’ which represent continuity of the surface. Examples are presented to demonstrate selected situations. One limitation of the approach is that the velocity of the surface is not known as a function of the surface angle. Rather, it is known for the angles of the left and right segments. The rate as a function of angle must be assumed for the explicit integration procedure used. Numerical implementation is briefly discussed.

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