Dartford Tunnel West

Shotcrete was contracted to carry out five trial repairs on the perimeter barriers that also support the footpaths within the West Dartford Tunnel. Our scope of work included the controlled cutting and breakout of defective concrete sections, followed by the reinstatement of new barrier tops. The repair works were undertaken with careful consideration to retain and accommodate all structural and functional aspects of the existing barrier system. 

One of the major challenges we faced was reinstating the concrete in the limited space behind the panels.   The working area was extremely limited, further complicated by the presence of multiple cables and a tray, which created additional obstructions. 

Another key challenge involved integrating various structural and architectural elements, including accommodating the handrail posts, a newly added L bracket on the rear side, a horizontal load bar passing through the system, and several other components that had to align precisely with the new panel installation. 

To overcome these constraints, we sourced compact drills, allowing us to carry out precise drilling at the back of the panels for post drilling holes and building shutters. 

Through careful planning, we were able to anticipate potential risks early, particularly around conflicts with cast-in items and elements already incorporated into the structure. 

We had to develop a number of innovative solutions to successfully complete this job. From using specialist drills to operate in tight spaces, to creating custom lids for the shutters and manually flowing the concrete to prevent voids—every step required careful planning and adaptability. 

Throughout the project, we continuously refined our methodology with each panel. The team on site worked exceptionally well together, always looking for ways to improve and streamline the process.  

Their collaborative effort and commitment to quality made a real difference in delivering a successful outcome.