Abstract
In recent years, composites and plastics have been developed for some applications in railway industry. Clear examples are 'fibre-reinforced foamed urethane (FFU)', 'geopolymer concrete', 'recycled polymer', and 'CarbonLoc composite'. The development fundamentally takes advantage of timber-like dynamic properties with which the sleepers can sustain realistic track dynamic loading conditions and last much longer than concrete counterparts. Railway sleepers and bearers are critical for safe and reliable operations of railway switches and crossings. The deterioration process of sleepers depends largely on the materials of which they are made. The adoption of composite material as turnout bearers in railway switches and crossings has raised several concerns if they can cope with the exposure to aggressive environments. Importantly the dynamic properties of bearers influence the functional constraints and serviceability of the switches and crossings. Excessive turnout vibrations at switches can cause malfunction of crawlock or signalling gear systems. Although such the understanding into dynamics aspect is well-known, the actual effect of environmental variance on the dynamic properties of the bearers has yet been pointed out clearly. Inexperienced practition-ers are still confused about what properties they should use for analysis and design. The aim of this study is to identify the damping characteristics used for the design and practical selection of full-scale composite materials in railway turnout systems. The alternative composite material, 'fibre-reinforced foamed urethane (FFU)', is investigated since FFU has been used in several railway switches and crossings around the world. The dynamic damping of the FFU materials will be determined using the instrumented impact hammer testing method. The dynamic damping and natural frequencies of the full-scale specimens are determined from the FRF and vibration data in the frequency range between 0 and 1,600 Hz. These component-based dynamic properties are critical for mitigating track serviceability exposed to dynamic problems from wheel-rail irregularities and crossing impacts.
Original language | English |
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Title of host publication | Proceedings of the 26th International Congress on Sound and Vibration |
Editors | ICSV26 Local Committee in Montreal |
Publisher | Canadian Acoustical Association |
Number of pages | 8 |
ISBN (Electronic) | 978-1-9991810-0-0 |
Publication status | Published - 8 Jul 2019 |
Event | The 26th International Congress on Sound and Vibration: ICSV26 - Montreal, Montreal, Canada Duration: 7 Jul 2019 → 11 Jul 2019 http://icsv26.org/ |
Publication series
Name | International Congress on Sound and Vibration Conference series |
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ISSN (Electronic) | 2329-3675 |
Conference
Conference | The 26th International Congress on Sound and Vibration |
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Abbreviated title | ICSV26 |
Country/Territory | Canada |
City | Montreal |
Period | 7/07/19 → 11/07/19 |
Internet address |
Keywords
- composite material
- crossing impacts
- damping
- railway bearer
- vibration control