The HS2 Marston Box Bridge is a new bridge constructed as part of the UK’s High Speed 2 (HS2) rail project. The bridge was specifically designed to reduce construction time and minimise disruption to traffic on the underlying motorway, which is one of the busiest transport corridors in the region.
To achieve these objectives, the bridge structure was fully formed prior to installation and later slid into its final position. BrandSafway was involved from an early project stage, contributing engineering expertise and system solutions that enabled a highly efficient construction sequence and tight project schedule.
A major challenge of the HS2 Marston Box Bridge project was to construct and install a large box bridge structure while keeping motorway closures to an absolute minimum. This required a construction method that allowed most works to be carried out off-line, away from live traffic, and completed within a very limited installation window.
In addition, the formwork and shoring systems had to integrate seamlessly with the reinforcement design, ensuring structural integrity while supporting fast assembly and striking times. Achieving this level of coordination demanded early involvement in the planning phase and close collaboration between all project stakeholders.
BrandSafway’s early participation in the project made it possible to align the formwork, shoring and reinforcement design from the outset. The reinforcement layout was adapted to incorporate tie holes for the MANTO® G3 wall formwork, enabling efficient and precise construction of the bridge structure.
The bridge deck was supported using GASS® shoring, providing the required load-bearing capacity and stability during casting. Once construction was complete, the fully formed bridge was slid into its final position over a 40-hour period, making this project the longest box slide in Europe. This approach significantly reduced on-site installation time and ensured that closure of the busy motorway was kept to a minimum, meeting both technical and logistical project goals.
