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Young Curly Brunette Girl With High Heels Reveals Her Orange Top On The Bridge At The Railway Track
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For much of the 20th century, railroad track used softwood timber ties and jointed rails, and considerable extents of this track type remains on secondary and tertiary routes. The rails were typically of flat bottom section fastened to the ties with dogspikes through a flat tieplate in North America and Australia, and typically of bullhead section carried in cast iron chairs in British and Irish practice.
Jointed rails were used, at first because the technology did not offer any alternative. However the intrinsic weakness in resisting vertical loading results in the ballast support becoming depressed and a heavy maintenance workload is imposed to prevent unacceptable geometrical defects at the joints. The joints also required to be lubricated, and wear at the joint bar (fishplate) mating surfaces needed to be rectified by shimming. For this reason jointed track is not financially appropriate for heavily operated railroads.
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