The refurbishment of 18 railway bridges, part of the longest new domestic railway to be constructed in Britain for over 100 years.
The scope of works included:
- The design, provision and installation of bespoke access scaffold, suitable for all trades to work from during grit blasting, painting, surveying, steel strengthening, steel component replacing, installing hardwood timber ballast retention systems and new walkways with handrails.
- The vast range of bridge types on The Borders Railway, varied considerably and each had its own unique challenges to overcome from a structural viewpoint. Hogs back girders were the order of the day on many of the structures, which meant each and every vertical stiffener was a different length to its neighbour. Bespoke templates were required in every location. Replacement cross girders had to be manufactured with an inbuilt installation tolerance so they could rotate between the pair of Parapet girders prior to being bolted up with suitable packers at each end.
- Bearing stiffeners (vertical) at each extreme end of the Hogs back girders were particularly intricate to template and manufacture. This was due to the tight radius at the top flange which had a design tolerance of ½mm. Installing fasteners in this location was very problematic due to existing stone pilasters at each of the piers. We perfected a system of “fishing” the Tension Control Bolts through the new bolt holes thereby eliminating the need to demolish the listed stone pilasters.
- Each structure was grit blasted to achieve an SA2.5 standard of cleanliness, before a 4 coat epoxy paint system was applied to provide a 25 year life expectancy. Given the structure’s sensitive surroundings we utilised our closed circuit waste retrieval system; ensuring all lead contaminated abrasive was removed via vacuum skips, preventing any leakage to the local environment.
During the 1960’s over 5,000 miles of railway lines and associated stations were closed as a cost cutting and re-shaping program, the Borders Railway was one of them. Taziker Industrial were engaged by Principal Contractor BAM Nuttall to provide scaffolding, strengthening works, grit blasting, painting, installing new ballast retention timbers and providing and fitting new access walkways to 18 structures along the new Tweedbank to Edinburgh Waverley line.
Without maintenance for over 40 years, many of the structures had been reclaimed by their surrounding environment and required significant repairs and additional strengthening components to meet the challenging requirements of today’s railway.
In many instances our various departments worked 7 days per week, which was required to maintain the programme milestones. By planning our works carefully, we were able to ensure we could make the most effective use of our time during these work periods. This allowed us to open the structures on time, and to programme, allowing for the critical passage of heavy construction traffic throughout the project.
The BAM Nuttall team specifically cited our ability to provide a complete service and our technical expertise as key factors in their decision to award the works to TI. They also understand the value they receive from our provision of directly-employed staff. This enables the site to be managed in a consistent manner with better management of health, safety, environmental safeguards and improved overall communication with our principle Client. Progress meetings were held every week with Senior team members, from each area of expertise in attendance.
Learning and Innovation
Working within the confines of the Borders Railway extended sites was not without its problems. The potential for environmental incidents was discussed at each of our on-site meetings, to ensure each and every trade on site were made well aware of the biodiversity of wildlife, active around our worksites.
As a company, we engaged at all levels with our Client and took a particular interest in any comments from the onsite Ecologists
Delaying our works in many instances where birds were nesting on bridges or in close proximity to any work sites. Ensuring our materials storage areas were far enough away from Badger Sets, Otter Hovers or Holts, ensuring materials, grit or overspray could not foul Gala Water, and pollute what is a valuable Salmon habitat.
Our Envirowrap which encapsulated our worksites as a whole were inspected daily for wind or tear damage.
Our toolbox talks focused not only health and safety at work but also on the delicate balance of nature within our horizon.
The extra care and attention we focused on, ensured the environment did not suffer by our passing through.