One drawback of operating a heritage railway as old as the NYMR is that its infrastructure only has a finite lifespan.This is particularly true of the large girder bridges we have, which in some cases are well over 100 years old and are carrying heavier loads than they ever carried in pre-preservation days.We have already replaced the largest, Bridge 30, and now three at Goathland need attention.

Bridges 27, 25 and 24 to the south of Goathland were installed in 1908, and even back then were second-hand; the original spans that formed Bridge 27 now form Bridge 25.They are made of metal, and after more than a century of use they are starting to show their age. While they are in no danger of falling apart or collapsing, we must consider their repair and/or renewal in the next five years.

Bridge 27

Bridge 27 is suffering the most; extensive corrosion and wasting away of significant parts of the early steelwork is a particular problem. The increased use of heavy axle- load steam engines leads to increased stresses in some of the bridge deck components, all of which are heavily corroded.While there is often a degree of redundancy in early bridge design that enables a structure to cope with today’s loadings, in this case there are some areas of concern.

One particular area of corrosion is in the top flanges of the main girders, especially where they have extra doubler plates provided to strengthen them.

When we reconstructed Bridge 30, which had also been strengthened in 1908 by the same contractor, we found some quite large sections of wrought iron plate mixed in with what had been specified as ‘steel’.

Wrought iron has a significantly lower permissible working stress loading than steel, which coupled with this corrosion in the main girder flanges increases our concerns for the remaining strength and durability of the bridge under live load.

Therefore after careful consideration and review of the condition and structural assessment, we believe this bridge is now past economic repair if it is required to continue to carry heavy steam locomotives. It is proposed that the complete renewal of the running line part of the bridge be progressed using a new two track modern standard welded bridge, but with false rivets on the main girder top flanges and end plates.

Bridges 24 and 25

Bridge 24 lies approximately ¼-mile south of Goathland station, carrying the railway with a skew span of 61ft over the Eller Beck and a farm access road.When built in 1865 it carried two tracks, but in 1908 it was reconstructed and converted into two single line bridges side by side.The former Up Line span now carries the NYMR’s bi-directional running line.

An initial engineering structural assessment indicates that there are some significant design weaknesses in the connections between the cross girders and main girders. The necessary strengthening has already been done on nearby Bridge 25, which sits between Bridge 24 and Goathland station, again carrying the railway over the Eller Beck with a square span of 59ft 11in.

In spite of this it is felt that both Bridges 24 and 25 both require remedial work to ensure that they can continue to be used by passenger trains hauled by large heavy steam engines.

One particular problem is that, on both bridges, the middle main girders are very close together with almost no space in between to inspect or maintain them.There are various options which can be looked at to enable the repairs and strengthening work to be carried out, which would also make provision to minimise future fatigue problems.

The target date to invite tenders for the site works would be 1st September 2019 with the contract let by 1st June 2020 and the works programmed over the following two years.We have identified budget costs of £500,000 for the works on Bridge 24 and £400,000 for Bridge 25.

Our bridges are crucial to remaining an operating railway. Please help us with the biggest challenge that remains to making our route sustainable for the next half century.’


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