Finite Element Analysis of Rail-End Bolt Hole and Fillet Stress on Bolted Rail Joints

2017 ◽  
Vol 2607 (1) ◽  
pp. 33-42 ◽  
Author(s):  
Kaijun Zhu ◽  
Yu Qian ◽  
J. Riley Edwards ◽  
Bassem O. Andrawes
Keyword(s):  
Finite Element ◽  
Vertical Displacement ◽  
Rail Transit ◽  
Rail Transportation ◽  
Element Analysis ◽  
Transit System ◽  
Transit Systems ◽  
Service Failures ◽  
The University ◽  
Continuously Welded Rail

A rail joint typically is one of the weakest elements of a track superstructure, primarily because of discontinuities in its geometric and mechanical properties and the high-impact loads induced by these discontinuities. The development of continuously welded rail has significantly reduced the number of rail joints, but many bolted joints remain installed in rail transit systems. Because of the unique loading environment of a rail transit system (especially high-frequency, high-repetition loads), defects related to bolted rail joints (e.g., joint bar failures, bolt hole cracks, and cracks in the upper fillet) continue to cause service failures and can pose derailment risks. Recent research in the Rail Transportation and Engineering Center at the University of Illinois at Urbana–Champaign has focused on investigating crack initiation in the bolt hole and fillet areas of bolted rail joints. Stress distribution was investigated at the rail-end bolt hole and upper fillet areas of standard, longer, and thicker joint bars under static loading conditions. Numerical simulations were organized into a comprehensive parametric analysis performed with finite element modeling. Preliminary results indicated that the longer joint bar performed similarly to the standard joint bar but the thicker joint bar reduced rail vertical displacement and rail upper fillet stresses compared with the standard joint bar. However, the thicker joint bar also may generate higher stresses at the rail-end bolt hole. Additionally, joint bar performance was dependent on the rail profile and bolt hole location.

Assessing the Existing Bursa Light Rail Transportation System

2020 ◽  
Vol 2674 (10) ◽  
pp. 250-260
Author(s):  
Mehmet Rizelioğlu ◽  
Turan Arslan
Keyword(s):  
Traffic Congestion ◽  
Transportation System ◽  
Transportation Systems ◽  
Bus Rapid Transit ◽  
Light Rail ◽  
Rail Transportation ◽  
Transit System ◽  
Transit Systems ◽  
Negative Impacts

As car ownership soars, traffic congestion and its associated negative impacts have become real concerns in many cities around the world. Therefore, transportation systems that perform better in eliminating or reducing traffic congestion and related problems to tolerable levels have become imperative. Alternative transit systems should be assessed properly to accommodate the expected demand in the long term, at least, to some significant extent. However, this is generally neglected in developing countries and, among many possible alternatives, a popular transportation system is usually preferred within the available budget. As an example, Bursa Metropolitan Municipality, Turkey, has recently implemented a light rail transportation system (LRT) on its major east–west corridor as the main transit system. In this study, the existing LRT is assessed and its performance is compared with a hypothetical bus rapid transit (BRT) system, which is a strong contender and comparatively a lower-cost alternative. This is done to assess whether the LRT was the better choice in relation to the current demand. Therefore, in this study, the existing LRT system is first defined in the PTV VISSIM simulation environment. Then, the hypothetical BRT system is considered on the same route with the current demand. The capability and capacities of the existing LRT and the BRT system are assessed and compared in many aspects. The results are compared, and important findings are outlined.

scholarly journals Finite element analysis of T-joint of mechanical connecting channels

2020 ◽  
Vol 12 (12) ◽  
pp. 168781402097774
Author(s):  
Jiawei Wang ◽  
Fachao Li ◽  
Zibo Chen ◽  
Baishu Li ◽  
Jue Zhu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Three Dimensional ◽  
Rail Transit ◽  
Force Analysis ◽  
Analysis Model ◽  
Element Analysis ◽  
Finite Element Analysis Model ◽  
Before And After ◽  
Design Software

This paper studies the force and deformation of the connecting channel in Ningbo rail transit construction, which firstly used the mechanical shield method. Steel-concrete composite structural segments are used in the T-joint of connecting channel. The cutting part of the segments are replaced by the concrete and fiberglass instead of reinforced concrete. Basing on a variety of three-dimensional design software and ABAQUS finite element analysis software, a refined finite element analysis model of the special segments is established. By considering the influence of curved joint bolts, the force analysis of the special segments under the structural state before and after construction is performed. According to the analysis and comparison of the deformation of the segments with and without the bolts, it is concluded that the steel-concrete segments can withstand the pressure of the soil before and after the construction. Suggestions for the safety of the design and construction of the segments are put forward.

scholarly journals Flywheel vs. Supercapacitor as Wayside Energy Storage for Electric Rail Transit Systems

Inventions ◽  
2019 ◽  
Vol 4 (4) ◽  
pp. 62
Author(s):  
Mahdiyeh Khodaparastan ◽  
Ahmed Mohamed
Keyword(s):  
Energy Storage ◽  
Energy Saving ◽  
Voltage Regulation ◽  
Appropriate Technology ◽  
Rail Transit ◽  
Peak Demand ◽  
Transit System ◽  
Transit Systems ◽  
Industrial Sectors ◽  
Demand Reduction

Energy storage technologies are developing rapidly, and their application in different industrial sectors is increasing considerably. Electric rail transit systems use energy storage for different applications, including peak demand reduction, voltage regulation, and energy saving through recuperating regenerative braking energy. In this paper, a comprehensive review of supercapacitors and flywheels is presented. Both are compared based on their general characteristics and performances, with a focus on their roles in electric transit systems when used for energy saving, peak demand reduction, and voltage regulation. A cost analysis is also included to provide initial guidelines on the selection of the appropriate technology for a given transit system.

Validation of Sleeve Weld Integrity and Workmanship Level Development

2006 ◽  
Author(s):  
Robert Lazor ◽  
Brock Bolton ◽  
Aaron Dinovitzer
Keyword(s):  
Finite Element ◽  
Numerical Models ◽  
Full Scale ◽  
Loading Conditions ◽  
Element Analysis ◽  
Service Failures ◽  
Applied Loading ◽  
Fea Modeling ◽  
Field And Laboratory Conditions ◽  
Scale Data

Full encirclement repair sleeves with fillet-welded ends are often used as permanent repairs on pipelines to reinforce areas with defects, such as cracks or corrosion. In-service failures have occurred at reinforcing sleeves as a result of defects associated with the sleeve welds, such as hydrogen-induced cracks and undercut at the fillet welds, inadequate weld size, and sleeve longitudinal seam ruptures. This work was undertaken to support the development of tools for sleeve design and for conducting an engineering assessment to determine the tolerable dimensions of flaw indications at full encirclement repair sleeves. In particular, the project was intended to validate the stresses estimated using finite element analysis (FEA) models against actual in-service loading conditions experienced at reinforcing sleeves. The experimental work focused on the collection of full-scale experimental data describing pipe and sleeve strains for the following field and laboratory conditions: • Strains induced by sleeve welding, • Strains induced by pressurization of the sleeved pipe, • Strains induced by pressurization of the sleeved pipe and the annulus between the pipe and sleeve. Finite element models of the field and laboratory sleeved pipe segments were developed and subjected to the same applied loading conditions as the full-scale sleeved pipe segments. Comparisons of the measured strains against those estimated using FEA were completed to determine the ability of the models to predict the behaviour of the sleeved pipe segments. Comparisons were made to illustrate the relative strain levels and deformation trends, the accuracies of the strain predictions and trends in changes with pressure, the differences in behaviours between tight and loose fitting sleeves, and the effects of pressurizing the annulus between the pipe wall and sleeve. The analysis of the field data and FEA modeling predictions led to several conclusions regarding to use of numerical models for predicting sleeved pipe behaviour and weld flaw acceptance: • FEA results demonstrated behaviours that were consistent with full scale data, • Trends in the FEA predicted strains agreed with the full-scale data, • FEA models describing the effects of gaps between the pipe and sleeve and annulus pressurization agreed with field experience and engineering judgment, • Evaluation of the significance of root and toe flaws can be completed by extending the models validated in this work.

Assessing Transit Changes in Columbus, Ohio, and Sacramento, California

2005 ◽  
Vol 1930 (1) ◽  
pp. 62-67 ◽  
Author(s):  
John Schumann
Keyword(s):  
Federal Funding ◽  
Light Rail ◽  
Rail Transit ◽  
Transit System ◽  
Transit Systems ◽  
Bus Transit ◽  
The Past ◽  
Voter Approval ◽  
Capital Funding ◽  
Bus Service

This paper compares the changes experienced by transit systems in two state capitals of similar size: Columbus, Ohio, and Sacramento, California. Over the past two decades, Sacramento added a light rail transit (LRT) starter line and experienced significant ridership growth on its multimodal rail and bus system, while Columbus remained all-bus and experienced a decline in patronage. Reasons underlying the divergent performances of these two systems are analyzed and discussed. It is concluded that, in Sacramento, willing political leadership took good advantage of a one-time opportunity for federal funding to build an LRT starter line; that adding LRT made transit more visible and effective and encouraged voter approval of additional local operating and capital funding; and that all of this resulted in a synergy that attracted more riders to the total LRT and bus transit system and led to extension of the rail system to a third corridor in 2003. Although planning for LRT was begun in Columbus during these same years, a serious interruption in the flow of local funds hampered transit development, required cuts in bus service, and prevented development of that region's planned LRT line. Columbus currently has an LRT project in preliminary engineering, and recent reports suggest a consensus to proceed may be emerging.

Study of the Critical Load for Rigid Airport Pavement by the Finite Element Analysis

2012 ◽  
Vol 204-208 ◽  
pp. 1748-1753
Author(s):  
Jing Cai ◽  
Zong Bao Yue
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Critical Load ◽  
Vertical Displacement ◽  
Slab Model ◽  
Analysis Model ◽  
Element Analysis ◽  
Finite Element Analysis Model ◽  
Airport Pavement ◽  
The Finite Element Analysis

In the airport pavement design, the critical load position has the guiding significance for the airport pavement slab design. The finite element analysis model of rigid airport pavement is built, and 2-slab model and 9-slab model are analyzed. The corresponding load positions are obtained when the maximum stress and the maximum vertical displacement happen

Moisture Content's Influence to Pile Bearing Capacity and Finite Element Analysis

2014 ◽  
Vol 633-634 ◽  
pp. 922-926
Author(s):  
Li Hua Zhang ◽  
Li Yu ◽  
Zhe Jun Quan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Moisture Content ◽  
Bearing Capacity ◽  
Unsaturated Soil ◽  
Vertical Displacement ◽  
Relative Displacement ◽  
Engineering Practice ◽  
Element Analysis ◽  
Lateral Extrusion

This essay analyzes stress between pile and soil, occupying moisture content data of unsaturated soil in Nanchang with ANSYS. In accordance with engineering practice, it adopts three-dimensional solid model, the same geometric size with engineering practice. It simulates interrelation between pile and soil with contact unit, and shows ontology relation of soil with D-P elastic-plastic model. Convergence has been made with selection and calculation of parameter. The greater the moisture content gets, the smaller the pile body vertical displacement makes. In other words, the smaller the relative displacement between pile and soil gets, the lower the lateral extrusion stress from pile to soil becomes. Keywords: unsaturated soil; shear strength; pile bearing capacity; finite element analysis; moisture content

The Hangover: Assessing Impact of Major Service Interruptions on Urban Rail Transit Ridership

2017 ◽  
Vol 2648 (1) ◽  
pp. 79-85
Author(s):  
Julene Paul ◽  
Michael J. Smart
Keyword(s):  
New York ◽  
Urban Areas ◽  
Hurricane Sandy ◽  
Urban Rail Transit ◽  
Rail Transit ◽  
Transit System ◽  
Transit Systems ◽  
Service Interruptions ◽  
Transit Ridership ◽  
Transit Agencies

Driven by several factors, transit ridership has increased dramatically in some major U.S. urban areas over the past several years. Developing accurate econometric models of system ridership growth will help transit agencies plan for future capacity. As major weather events and maintenance issues can affect transit systems and have large impacts on the trajectory of ridership growth, this study examined the effect of major and minor service interruptions on the PATH heavy rail transit system in northern New Jersey and New York City. The study, which used PATH ridership data as well as data on weather, economic conditions, and fares for both PATH and competing services, concluded that Hurricane Sandy likely dampened ridership gains. Other major service interruptions, which lasted only hours or days, had little effect on long-term ridership growth. Suggestions for further study of service interruptions, especially in the face of climate change and resiliency issues in coastal regions, are presented.

Stress Analysis of Grain Steel Silo with Hole

2012 ◽  
Vol 594-597 ◽  
pp. 666-671
Author(s):  
Qi Feng Peng ◽  
Fan Wang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Service Life ◽  
Circular Hole ◽  
Stress Level ◽  
Vertical Displacement ◽  
Principal Strain ◽  
Element Analysis ◽  
The Impact

The stress of the grain steel silo is complex. Recently, many grain silos scraped during their service life. The results of finite element analysis by COMSOL show that the cause of the structure failure is the stress concentration caused by the expanding of the hole. Analysis on different hole on the wall of the silo and different frame to strengthen the hole was also studied. Considering the impact of the weight of the structure, the pressure and friction force caused by the storage of the grain and wind load. The analysis turn out that, if the frame of the hole is identical, the stress level and the first principal strain in condition of circular hole is lower than that of rectangular condition, and the maximum vertical displacement of circular hole is smaller than rectangular. In addition, if the hole is the same, the stress level and the first principal strain in condition of U-shaped frame is lower than that of square condition, but the maximum vertical displacement U-shaped frame is bigger than square frame. Therefore, we can’t reduse the stress level by strenthening the frame.

A deep retaining structure in till and sand. Part II: Performance and analysis

1983 ◽  
Vol 20 (1) ◽  
pp. 131-140 ◽  
Author(s):  
Z. Eisenstein ◽  
L. V. Medeiros
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Case History ◽  
Lateral Pressure ◽  
Stress Strain ◽  
Element Analysis ◽  
Transit System ◽  
Ground Movements ◽  
Retaining Structure ◽  
Analytical Results

The problem of magnitude and distribution of lateral pressure acting on a deep retaining structure supporting an excavation in till and sand is studied by an approach integrating field measurements from a case history with a finite element analysis. Also studied are ground movements associated with the excavation. The finite element analysis is based on stress path dependent testing of the soils involved.The case history is the behaviour of a deep supported wall of the underground Churchill Square Station of the recently built line of the Light Rail Transit System in Edmonton. A tangent pile wall, 17 m deep, has been placed through glacial till to underlying sands. The site has been instrumented to record displacements of the wall and of the surrounding ground as well as the loads carried by the lateral supports.A finite element analysis employing several stress–strain models was used to simulate the excavation and its sequence, the placement of lateral support, and the differential stiffness of the structural components and of the surrounding soil. Special attention has been given to the effect of different stress–strain models of soils, with a particular focus on the influence of stress paths typical for the studied structure.Agreement between the field and analytical results for displacements is accepted as a criterion of validity of the analytical results of stresses, where direct in situ stress measurements are difficult to obtain and interpret. Of special importance is the calculated lateral pressure against the wall and its relation to the stiffness of the wall and to the magnitude of associated ground movements. The calculated lateral pressure has been found to differ significantly from the semiempirical design pressure diagrams used in practice.The soil stress–strain model found to describe the field behaviour most closely has been derived from test results obtained using a plane strain apparatus. Keywords: deep supported excavation, displacement, lateral pressure, field measurement, finite element analysis.

Sign in / Sign up

Export Citation Format

Share Document