Determination of load path through concrete crosstie and fastening system: a laboratory and field investigation

Wei, Sihang

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https://hdl.handle.net/2142/97369 Copy

Description

Title

Determination of load path through concrete crosstie and fastening system: a laboratory and field investigation

Author(s)

Wei, Sihang

Issue Date

2017-04-20

Director of Research (if dissertation) or Advisor (if thesis)

Kuchma, Daniel A.

Doctoral Committee Chair(s)

Lange, David A.

Committee Member(s)

• Spencer, Billie F.
• Andrawes, Bassem O.
• Edwards, John Riley

Department of Study

Civil & Environmental Eng

Discipline

Civil Engineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• Railroad
• Concrete crosstie
• Fastening system
• Load path
• Experiment
• Finite element analysis
• Static
• Dynamic

Abstract

US railways move more freight (measured in tonne-kms) by rail than by any other means. This is done over an extensive network of primarily private freight railway lines that also transport passenger trains. To enable the expansion of high-speed passenger rail service using shared passenger/freight infrastructure, the US Department of Transportation Federal Railroad Administration (FRA) sponsored a research project to investigate infrastructure design and performance challenges. This is a multi-faceted research project for which one element is laboratory and field investigation of the load path from rail-wheel to precast concrete crossties. In this research, the behavior of crosstie and fastening system is investigated through material-level, component-level and system-level laboratory and field experiments. The system-level experiments use three primary test setups. One of these setups, referred to as a static single-crosstie and fastening system experiment, enables the application of a downward and outward lateral force from the contact point of an idealize wheel through to the crosstie. Displacements and strains from each component were collected to understand the load path under simplified loading conditions. In addition to examining the factors that influence the flow of forces, a key objective of this work was to calibrate a means of displacement and strain measurements for use in rail corridors to determine the flow of forces from wheels through to crossties. The second test setup uses the full-scale Track Loading System (TLS) to conduct similar tests and measurements over a multi-crosstie system in laboratory. A 22-feet long section of track including eleven concrete crossties that was loaded by vertical and lateral actuators over a 32-inch wheel set with varying ratios of lateral to vertical force from the wheel to rail. The third test setup is the full-scale field experiment performed at the Transportation Technology Center (TTC) in Pueblo, CO. Five adjacent crossties in tangent and curved track were instrumented and loaded by Track Loading Vehicle (TLV) with static wheel loads. Dynamic tests were conducted with passenger and freight train consists at various speeds. Measurements including the wheel-rail interaction forces, rail seat vertical reactions, shoulder lateral reactions, and component strain and displacements. The data collected from the three system-level experiments was used to clarify the load path, target areas of uncertainty, investigate the behavior of each component under extreme static loading and cyclical dynamic loading, as well as calibrate and validate a 3-D finite element model being developed at UIUC. In addition, this research offers suggestions for the instrumentation, testing, data-analysis and current design recommendations of concrete crosstie and fastening systems.

Graduation Semester

2017-05

Type of Resource

text

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http://hdl.handle.net/2142/97369

Copyright and License Information

Copyright 2017 Sihang Wei

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