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:''This article is about the types of railway track technologies known as Ladder Track. For a description of the track layout also known as ladder track, see the description in Classification yard.'' Ladder track is a type of railway track in which the track is laid on longitudinal supports with transverse connectors holding the two rails at the correct gauge distance. Modern ladder track can be considered a development of baulk road which supported rails on longitudinal wooden sleepers. Synonyms include longitudinal beam track. ==History and overview== Ladder type track has also be used historically on bridges lacking ballast, and in situations requiring good drainage or ease of maintenance such as stations.〔 Described as track with longitudinal bearers with cross ties, ladder track type was common on early British railways (c.1830/40s), including the Birmingham and Gloucester Railway, Dublin and Kingstown Railway, Glasgow, Paisley, Kilmarnock and Ayr Railway, Great Western Railway (see Baulk road), Ulster Railway, Newcastle and North Shields Railway, Slamannan Railway (part of), Hull and Selby Railway (two thirds of), Manchester and Bolton Railway (including lontudinal stone sleepers), and the London and Greenwich Railway (partly).〔 , (alt. link )〕 On the Hull and Selby Railway it was used in part as it was noted to produced smooth running, and low wheel wear. However the contact between rail and sleeper produced hydraulic pumping in wet conditions, which led to rolling stock becoming dirtied very quickly. The longitudinal track was also found cause issue with wheel slip on inclines, and to be noticeably inferior to transverse sleepered track in terms of traction. No longitudinally laid track remained on the line after 1860.〔 Research into longitudinal sleepers took place in Japan, Russia and France in the mid 20th century. In the late 20th century, interest in ladder type tracks increased due to its potential for lower cost and lower maintenance railways, as well as increased stability benefits over sleepered track. In general, ladder track produces lower pressures on the road bed: both the maximum pressure and the amplitude of pressure pulses are smaller than transverse sleepered track, which can reduce maintenance costs in ballasted systems. An additional benefit in ballasted ladder track is increased resistance to ballast wash out and other forms of ballast degradation due the addition longitudinal support and rigidity in ladder track.; the same structural rigidity also adds to buckling resistance.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ladder track」の詳細全文を読む スポンサード リンク
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