Brunel's Other Bridge

Brunel Swivel Bridge Project 2015

Rust on the turntable

Rust on the base of the bridge Completed test patch

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• Carry out clearing of vegetation and debris from the area under the deck,
• Continue with the preparation/fitting of the two timber stops, being led by Graham Laucht,
• Continue with outstanding survey work, being led by Bob Watkins,
• Excavate the area adjacent the south-east side of the cast iron bed to establish the extent and depth of the concrete footing,
• Continue to remove welded patches over holes so that we can measure plate thicknesses.
• Possible painting if we find worrying 'new' rust.

Mike delved down a meter below ground to clear the pits housing the huge timber stops that prevented the bridge over-running. He then installed two giant timbers prepared by Graham who came down specially from Birmingham with his car loaded to the gunwales with two enormous 12 x 12 inch baulks! Thanks Graham, and we hope your back is soon better.

Meanwhile Geoff cut the raking end of the 12 x 12 inch timber prop for the stop......mostly by hand-saw! (Yes, honestly)

Maggie photographed, manned our exhibition stand, fielded questions from our numerous visitors and captured their e-mail addresses as supporters, whilst also doing 'gardening' with Ros to clear weeds, moss etc.

Bob and Martyn's long-running and detailed survey of the condition of plate-work was finished on Sunday. They couldn't put off any longer the uncomfortable task of laying on their back and peering up under the side beams, hammering the plates to check for holes. Geoff removed three welded-on patch-repair plates revealing more holes and allowed the thickness of surviving platework to be measured. Bob now has some 'winter-work' at home to complete the CAD drawings.

Finally, as a treat on Sunday afternoon our happy group gathered under the temporary roof which was transformed into a little cinema. Sal showed us an eight minute video called 'Triangulation', produced by Ruben Knutsen, commissioned for the Brunel 200 celebration in 2006, in which local celebrity Tony Bailey performed a contemporary dance on the Swivel Bridge before the timber deck was removed. what an interesting and fitting conclusion to our 2015 season of voluntary work!

If you wish you had joined in our fun, its not too late as we start up again in March next year, so please check out our web-site for monthly work-dates and come and join us.

• General tidy up, remove vegetation, etc.
• Continue to grind off plates welded over holes.
• Wire brush and paint areas around removed plates and elsewhere.
• Continue to shape the new timber 'stop' to replace the rotten one under the Plimsoll Bridge.
• Start excavating the footings around the tail-wheel track and back-fill on completion.
• Help Bob with the plates surveys.

Bob, Martyn, Sharon and Yasin completed the plate-work survey, and then we all focussed on excavating the tail-wheel track to see if we could establish how it is supported. A drawing shows timber beams and piles, so that is what we expected, but as we dug down all we found was concrete, and more concrete. We did, however also find a stone-capped drain running towards the line of another known drain, but its purpose remains a mystery.

The Bridge is Grade 2* listed so archaeological work must be supervised by a qualified archaeologist. Volunteer Mike Chapman therefore joined us, which was very much appreciated Mike.

We established that the built-up ground under the track is clay, probably dumped there during the excavation of the present Entrance Lock, covered by a layer of late Victorian fill, which included broken pottery and a clay-pipe fragment. The track itself rests on a mass concrete beam at least 4ft deep and a similar width. We tried to cut into this to seek hidden timber beams, but were defeated by amazingly hard concrete, so we photographed and measured everything, back-filled the excavation and tamped the ground flat.

• Finish the roof
• Take off some of the repair plates welded over holes which involves grinding
• Clean and paint the rusted areas underneath
• Clean out the ram-pits and turntable pits again.
• Complete the re-installation of the ram that was taken out for inspection.
• Prepare a drawing of the timber stop at the tip of BOB and dismantle it ready for re-erection.
• Anything that Bob needs us to do to assist his surveys.

On Sunday we welcomed two new volunteers Katarina and Reece. Bob's team continued the condition survey of the rusted plate-work whilst Geoff's team erected the timber frame of the eastern half of the roof to protect the vulnerable turntable structure. This will be completed in May.

1. Erect the temporary roof.
2. Bob's survey work.
3. Complete the interpretation boards
4. Prepare drawings for a new timber stop to replace the decayed existing one. We can start preparing the timber for this too.
5. Start removing welded-on steel patches.

Bob and four new engineering volunteers continued with the condition survey, this time focusing on the numerous transverse beams that run across the Bridge, whilst Mike B and Maggie erected our two smart new interpretive boards. People were stopping and reading them as soon as they were finished, and they proved very popular.

Maggie, two Mikes, Graham and Geoff focused on erecting the first 3m long section of the felt-clad roof to protect the highly-stressed wrought iron girders that support the entire structure. They are severely corroded and the new roof will buy us time whilst we seek funding to restore the Bridge fully. The roof is strongly constructed of 150 x 50 timbers with a plywood and glued felt covering, all tied down with steel cables to prevent the whole lot blowing away in a high wind. Meanwhile our wonderful volunteer Julian from the Bristol Film and Video Society recorded our progress.

9th January: Maggie, Mike, Geoff, Bob and Martyn fixed long boards to allow safer access to the deck of the Bridge. Julian Baldwin from the Bristol Film and Video Society (BFVS) came to film the project because they considered that this restoration was of sufficient importance in terms of local engineering history to warrant being filmed during its progress to produce an enduring record of the project.

11th January: Bob, John Cook, and Tom Aylott braved the cold weather on Sunday to survey, with Julian Baldwin from BFVS in attendance to record the scene. Surveying the structure is another vital task which will allow detailed planning of the restoration works.

12th January: Repair-plates going in on the bottom triangular section of the south side-beam. The four bolts are special high-strength friction-grip bolts put in with a pneumatic gun that tightens them by means of a spigot on the end that breaks off when the bolt is tight enough. They are very effective, and we are condidering using them where we can't get in to rivet.
One of Dorothea's staff in protective gear spot-blasted the underside prior to painting. He was using a hard grit called aluminium oxide which scours away the rust but not the wrought iron. So,the repairs substantially finished this week, weather-permitting, and a small proportion of the Bridge has already been blast-cleaned and painted! .

17th January: Mike Bone, Geoff Wallis and Maggie showed Underfall Yard's new Community, Learning and Volunteers Manager Sarah the features of the bridge today. Very icy, but our new boards worked very well. We warmed up in the cafe, and then went a walkabout around the immediate area.

19 January: Closing up the trial holes. New rivets being replaced in small sections of the bridge which were removed to check the structural condition.