Winter Works 2018 / 19
Page updated on: 04/02/19
February 4th 2019
The work on the viaduct is progressing well thanks to continued favourable weather. The gaps that had been left by the rotted out shuttering from the 1970’s have all been filled with a shrink compensated grout which consumed over 80 bags of raw material. Specialist rope access contractors attended to fit and seal the new drainage pipes and kindly removed a large quantity of ivy from the structure with the spare time left over from the booked day. The levels around the inside of the drainage pipes have had additional concrete introduced to encourage rainwater to escape into the brook below. One unexpected item that has required rectifying was some outward movement of the south end parapet walls where a 10mm gap was detected. In order to remedy this, a block of mass concrete has been installed to transfer loads down into the south pier and away from the walls. An additional tie rod has also been fitted at the same time to prevent any further movement. The job of back filling has commenced with free draining material both recycled and new back up to track level. Volunteers from the signal department are to install ducts over the signalling cable in preparation for the final layers of backfill. One detail item which the contractors will be installing as part of the works will be replacement fencing for the previous wooden version which was life expired and of a non-railway design. Although originally there was no fencing over the structure, modern Health & safety concerns for line walkers means there needs to be some form of edge protection to prevent falls. New steel tube fencing of a style found elsewhere on the SVR will be installed and will give it a more appropriate appearance than before.
PW volunteers have been making up around 60 new wooden sleepers to use in the track relay the over the structure. These will help the viaduct by absorbing vibrations of passing trains and it is also planned to weld any rail joints located on the structure to remove the shocks caused when wheels pass over them.
The replacement of the two turnouts is proceeding well. The yard throat turnout is complete enough for limited movements to have taken place earlier this week. The condition of the original turnouts when removed has proved that the work is timely as they more or less fell apart. The new steelwork has been specially manufactured in Wales to order and the timbers are very good serviceable second hand from our usual supplier based in Worksop. The opportunity is also being taken to remove a misalignment in the track layout and should produce a much neater appearance. The work is due for completion on the 8th February so that the full time staff and volunteers can relay the track back across Borle viaduct in time for the planned stock movements prior to February half term running.
This is an unusual job requiring the partial replacement of the southernmost steel support column of the island platform canopy due to concerns about corrosion. The “I” section column was known to be rotten and some remedial work was carried out in the late 1970’s with the installation of a rather unsightly concrete block. The original canopy end screen has been removed and disposed of as it rotten and has a large section cut out for the concrete block. The contractor has found the original GWR mass concrete below the surface to be extremely resilient to the hydraulic pecker bought in to break it out. The decision has been taken that rather than remove something that is clearly still serviceable, the replacement column section will now be joined to the original below ground which is in excellent condition and encased in fresh concrete. The join above ground will be plated and bolted with dome head versions to replicate a riveted look. A brand new end screen section has been made and will be installed by joiners once the civils work is complete along with new cast iron rainwater drain pipes.
Chris Bond Infrastructure Manager
January 16th 2019
One of the main winter projects for 2019 is remedial works on Borle Viaduct which was highlighted in the 5 yearly line report as suffering from water penetration from above. This leads to erosion of the structure from freeze thaw action which is not good for its long term health. It is known that some work was carried out in the 1970’s by the then SVR civils team including the application of concrete to the top of the arches and the installation of tie bars to arrest the outward movement of the spandrel walls. After some 40 years it has become time to investigate why water has been circumnavigating the concrete and causing significant wet areas on the underside. After a competitive tender process, Stepnell Group were awarded the 6 week contract to carry out the job.
The first job was for our PW team to remove the track as soon as the engineering possession was granted and this duly took place on the 8th of January. The first task by the contractor was to scrape off the ballast for re-use later. Stepnell’s staff then rapidly started the task of removing the large quantities of fill material for depositing on the site of the former Kinlet Colliery sidings to the south of the viaduct. This is made up on a motley collection of ash, dirt and clay-like material, the best of which will be re-used when the viaduct is backfilled. The remaining dirt is then blasted clear using an air hose so that close visual inspection can be made of the existing concrete.
To date it has been found that when the concrete was installed in the 1970’s the edge of the area filled was shuttered and a mortar capping applied to seal it. Over the years this has failed and the shuttering rotted away. This has allowed water to get below the concrete and caused the water penetration that has been noted - the plan is to seal this gap with a suitable modern compound.
Generally the concrete is in good condition but will require adding to in places to create sufficient fall to the new drainage points that have been core drilled to provide a means of escape for rainwater. Interestingly, the wellington boot marks of those early SVR pioneers are preserved like dinosaur footprints in the 1970’s concrete and perhaps those who took part in the exercise may remember the vast quantities shifted by hand?
Once the repairs and fettling have been completed, the backfilling will begin with the aim of handing back to the PW in plenty of time to relay the track back across before the February half term running.
Chris Bond Infrastructure Manager
December 5th 2018
It may be a surprise to some that one of this winter’s projects has already taken place, namely a 600ft (or ten 60ft panels) track relay north of Arley near Bank Farm Crossing. The work was required due to the high number of poor quality concrete sleepers that had started to fail on this section and was carried out during two weeks of November. The track that replaced the original was flat bottom rail on steel sleepers and has effectively extended the existing flat bottom track northwards. The reason for this early relay is down to the other projects planned for the Jan/Feb shutdown and the need to have sufficient Permanent Way resources to do these.
The first of these projects will be the first phase in renovating Borle Viaduct. This was subject to waterproofing works back in the 1970’s and is now showing signs of fresh water penetration so requires rectification. A contract is being let for the removal of the fill material down to the existing concrete “flaunching” where any degradation will be treated and some additional drainage discharge points provided. The whole area will then have a high specification sealer applied before layers of new imported fill material is laid. The track will then be replaced and the whole lot ballasted and tamped. Although originally there was no edge protection on the viaduct, in later years sets of post and rail fencing has been used. This will now be replaced with more appropriate steel tubing fencing as used elsewhere on the SVR.
The second major project will be the second phase of turnout replacement in Kidderminster yard. The yard was laid many years ago using recycled components and during this period has probably experienced more traffic movements than anywhere else on the railway. Consequently, it is now totally worn out and action required. During the summer the turnouts that serve Carriage Shed siding 1 – 3 were replaced with virtually new materials and the severe curve into siding 1 eased. Due to the implementation of the next phase causing the isolation of the whole yard, it was decided to carry this out in the shutdown when usage is reduced (although not completely). Another two turnouts are due to be lifted scrapped and replaced as previously carried out. Hopefully the timing of these projects will run seamlessly into each other but even with careful planning the weather can make or break things.
Chris Bond Infrastructure Manager