scholarly journals Dynamic Analysis of Two-lane Skewed Bridge and High-speed Train System

2019 ◽  
Author(s):  
Meysam Jahangiri ◽  
Jabar Ali Zakeri
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
High Speed Train ◽  
Skew Angle ◽  
Modal Shape ◽  
Maximum Displacement ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
Skewed Bridge ◽  
Train System

Bridges are vital in the operation of railway networks since any hindrances to their operation could suspend the flow of traffic. An important characteristic of bridges highly affecting their behavior is the skew angle. In this paper, a sensitivity analysis is performed to identify the effects of skew angle on train-track interaction for single- and double-sided crossings of a high-speed train. Comprehensive three-dimensional finite element models of the bridge and vehicle are developed, which are then calibrated using dynamic field test results. Effects of skew angle on shape modes and modal frequencies, acceleration values, and bridge displacement in various crossing speeds are studied. The results showed that if the bridge skew angle is more than 15°, it will affect the modal shape and frequency of the bridge. When the skew angle is less than 15°, the results of the bridge displacement are similar to those of the bridge with skew angle of zero. However, with the increase of the skew angle, the deformation value of the bridge decreases and the speed corresponding to the maximum displacement value also varies. Finally, the results of acceleration due to the speed and skew angle of the bridge are not the same in one-way and two-way passing states.

Examination of Response of a Skewed Steel Bridge Superstructure During Deck Placement

2003 ◽  
Vol 1845 (1) ◽  
pp. 66-75 ◽  
Author(s):  
Elizabeth K. Norton ◽  
Daniel G. Linzell ◽  
Jeffrey A. Laman
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Analytical Models ◽  
Levels Of Analysis ◽  
Steel Bridge ◽  
Bridge Superstructure ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
Skewed Bridge

The response of a 74.45-m (244-ft 0-in.) skewed bridge to the placement of the concrete deck was monitored to compare measured and predicted behavior. This comparison was completed to ( a) determine theoretical deflections and rotations with analytical models for comparison to actual deformations monitored during construction; ( b) compare the results of various levels of analysis to determine the adequacy of the methods; and ( c) examine variations on the concrete placement sequence to determine the most efficient deck placement methods. Two levels of analysis were used to achieve the objectives. Level 1 was a two-dimensional finite element grillage model analyzed with STAAD/Pro. Level 2 was a three-dimensional finite element model analyzed with SAP2000. These studies are discussed and findings are presented.

Modelling of the laser surface nitriding of Ti-6Al-4V alloy—analysis of heat transfer and residual stresses

2001 ◽  
Vol 215 (3) ◽  
pp. 315-340 ◽  
Author(s):  
M Labudovic ◽  
R Kovacevic
Keyword(s):  
Residual Stresses ◽  
High Speed ◽  
Parametric Design ◽  
Three Dimensional ◽  
Laser Surface ◽  
Transient Temperature ◽  
X Ray Diffraction ◽  
Dimensional Finite Element ◽  
On Line ◽  
Three Dimensional Finite Element

A three-dimensional finite element modelling of the laser surface nitriding of Ti-6A1-4V alloy is presented. Design capabilities of ANSYS parametric design language (APDL) were employed for this purpose. The model calculates transient temperature profiles, the dimensions of fusion zone and residual stresses in the laser surface nitrided Ti-6A1-4V alloy. Model simulations are compared with experimental results, acquired on-line using an ultra-high-speed shutter camera which is able to acquire well-contrasted images of the molten pool, and off-line using metallographical and X-ray diffraction analyses which show very good agreement. The results are further discussed to provide directions for reducing the residual stresses, as well as for feedback and process control.

Numerical Analysis Technique to Estimate the Reliability of a Disc Brake System – Hot Judder Simulation

2012 ◽  
Vol 152-154 ◽  
pp. 723-726 ◽  
Author(s):  
Hyun Jung Do ◽  
Pil Jung Sung ◽  
Sun Chung Won
Keyword(s):  
High Speed ◽  
Hot Spot ◽  
Three Dimensional ◽  
Mechanical Analysis ◽  
Brake System ◽  
Disc Brake ◽  
Generation Process ◽  
Analysis Technique ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

Hot judder characteristics of a ventilated disc brake system are discussed. Three dimensional finite element models of the ventilated disc, pads and pistons are created, and a fully coupled thermo-mechanical analysis of the hot judder phenomenon of the disc brake system is performed using SAMCEF. The brake dynamo test is carried out according to the high speed judder test mode. The evolution of the temperature distribution on the disc surface is described, and the hot spot generation process is investigated. The simulation results such as the maximum disc temperature, BTV are compared to the data from the dynamo test, and the reliabilities of the analysis technique and simulation model presented in this paper are verified.

Three-Dimensional Finite Element Analysis on the Bearing Capacity of Bucket Foundation with Different Ratios of Diameter to Height

2014 ◽  
Vol 488-489 ◽  
pp. 689-695
Author(s):  
Shuai Liu ◽  
Wen Bai Liu ◽  
Liang Yang
Keyword(s):  
Bearing Capacity ◽  
Three Dimensional ◽  
Vertical Displacement ◽  
Ultimate Bearing Capacity ◽  
Displacement Curve ◽  
Maximum Displacement ◽  
Element Analysis ◽  
Bucket Foundation ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

The ABAQUS software is used for simulating the vertical bearing capacity of bucket foundation of different ratios of diameter to height and the analysis for the stress and displacement distribution and load-displacement curve. When the bucket foundation is under pressure, the vertical stress of the soil distribution changes from the bottom to the top, and then spreads to most part of the soil in the bucket foundation. The vertical displacement of the soil develops from the top of foundation and spreads inside, then expands to the outside range, the maximum displacement occurs both at the bottom and inside. According to the analysis of the ultimate bearing capacity of the bucket foundation, it could be found that when the height of the bucket foundation remains unchanged, the ultimate bearing capacity increases with the increasing ratio of diameter to height. If the ratio of diameter to height is less than 1.2, the ultimate strength increases significantly. If the ratio of diameter to height is greater than 1.2, the increasing speed of the ultimate bearing capacity changes slowly. When the diameter of the bucket foundation is constant, the ultimate bearing capacity decreases as the ratio of diameter to height gradually increases, and it decreases at a homogeneous speed. So the ratio of diameter to height 1.2 can be used as the optimum point of the ratio of diameter to height of the bucket foundation.

Sign in / Sign up

Export Citation Format

Share Document