File:1976-12 Railway Magazine p624.jpg

Summary[edit]

Tan-y-Grisiau gap bridged TIM CLARKE

THE week beginning July 19 was expected to be a hectic one for Festiniog Railway Deviation workers at the site of the future Tan-y-Grisiau Station, to meet the deadline of Tuesday, July 27, when delivery of the three main concrete beams for the new 50-ft. Afon Cwmorthin Bridge at the west end was due. During the week, the embankment on which the station and car-park will be sited had to be extended outwards some 60 ft. to accommodate the crane and a girder-bearing lorry side-by-side. Even though progress was hindered by breakdown for a day and a half of a crane, being used to supply rock from the east-end cutting, reasonable progress had been made by the weekend.

Work started at 07.30 on the Saturday, to complete enough embankment for a digger, which was hired from a local contractor, to provide road access for the main work three days later, and also to prepare for a load of graded stones to provide a suitable road-surface for the bridge-building.

On the Sunday the contractor made a smooth ramp up to the embankment suitable for the 60-ft. lorries which would be using it. Another 07.30 start on the Monday added some finishing touches, the top-stones were delivered and laid, and then there were just a few odds-and-ends to be done before the big day.

By 10.00 the first beam had arrived, and was waiting for the crane to lift it, which followed about an hour later. It was the largest mobile crane I have ever seen—16 wheels in contact with the ground, with four spare to go with it, and steering on four axles (the front three and the rear one).

The crane was parked near the beam on the roadside, while a conference on tactics was held, giving an unfortunate bus-driver quite a headache, though he just managed to squeeze past. However, the crane was manoeuvred to the end of the embankment, and the lorry carrying the beam was brought up alongside. This was when things started to go not according to plan, as it was discovered that the beam was the wrong way round. Anyway, with the last of the electricity wires down, it was time to start getting the beam into place. This was when the second setback occurred—a dispute as to whether or not the beam did actually weigh six tons as the six-ton straps on the crane were complaining.

After a short delay, during which Dow-Mac, makers of the beams, was contacted to find out the truth of the matter, with new lifting straps (this time for 18 tons!) the beam was put into place, following a quick twist—and a few heated words in the middle of the river—to get the beam the right way round. For the other two beams, however, the lorries reversed up the embankment to park only inches away from both crane and river bank, and operations went without hitch. The crane and empty lorries (now shortened to 30 ft.) were dispatched, and the temporary track was relaid ready to extend the embankment as far as progress of the east-end cutting allowed. With the beams in position, the long and intricate job of installing shuttering and reinforcing for the bridge decking could commence.