Temporary detour bridging to keep traffic moving in Scotland

Challenge

A £10 million Transport Scotland investment package was put in place to replace seven bridges along the A830 in Scotland. BEAR Scotland work on behalf of Transport Scotland to maintain part of the trunk road network in Scotland and were enlisted for the replacement bridge project.

The A830, also known as the ‘Road to the Isles’, is one of Scotland’s most scenic routes and provides vital infrastructure between Fort William and Mallaig. Due to the location of the sites and the lack of suitable diversion routes, BEAR Scotland decided that it was necessary to provide temporary diversion routes adjacent to the existing bridges during the replacement works. By doing so, it would help minimise disruption along the route.

An additional requirement for the project was that the temporary solution needed to be demountable and capable of supporting heavy loads.

Solution

Due to the varying spans required for each bridge site, a modular design was a major requirement. An 18 metre single span Mabey Compact 200™ capable of taking HA loading to BS5400-2: 2006 was chosen as the best option for the project due to its robust design and ability to be erected quickly.

To help with the installation of the temporary bridges, experienced site advisors offered support as and when required by BEAR Scotland. This meant that the bridges could be erected within a matter of days, allowing work to begin on the replacement bridge quickly and efficiently.

A crane-assisted launch was decided as the best option for the project as pre-installation construction could be done to prepare the area. This ensured that the bridge could be launched quickly and more cost-effectively.

Result

The Mabey Compact 200™ was an ideal solution for this project due to its ability to be dismantled, transported and reinstalled at different lengths. By providing a temporary solution, it meant that there was minimal disruption to the area and long diversions could be avoided. Through the success of the temporary solution, the bridge is now lined up to be used for future projects. The Mabey site advisors will continue to support BEAR Scotland when required.