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Cute Young Brunette Girl With A Green Scarf On The Railway Track
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Most railroads with heavy traffic use continuously welded rails supported by ties (sleepers) attached via tieplates (baseplates) which spread the load. A plastic or rubber pad is usually placed between the rail and the tieplate where concrete ties (sleepers) are used. The rail is usually held down to the tie with resilient fastenings, although cut spikes are widely used in North American practice.
Timber sleepers (ties) may be of hardwood or softwood, and are customarily treated with creosote or other wood preservative. Pre-stressed concrete sleepers (ties) are often used where timber is scarce and where tonnage and/or speeds are high.
The track ballast is customarily crushed stone, and the purpose of this is to support the ties and allow some adjustment of their position, while allowing free drainage.
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