Improvisation sees linkspan repair completed

It appears that a large cargo vessel was coming in to dock when it lost its position and impacted the support floats to the 120 tonne steel linkspan on the wharf. The supporting pontoon floats broke free and were dragged off, and eventually the bridge itself toppled and sank.

Within two weeks, Opus International Consultants had completed its inspection and reports which is “an incredibly rapid turnaround for marine infrastructure”, says Andy Traves, associate at the Fareham Office.

After meeting with the client, Associated British Ports (ABP), and loss adjusters for both ABP and the shipping line involved in the incident, Opus was then commissioned to schedule the repairs and replacements.

“For ABP, the key issue was to bring the linkspan back into action as soon as possible”, said Mr Traves.

However, getting it back into action quickly required some improvisation. The bridge is a modular system, and Opus sourced as many replacement components as possible from the United States. The challenge was that during the repair works, the team realised other components were also damaged. Not having time to put in a second order to replace these parts, the company decided to remove the undamaged parts of existing, on-site components and reconfigured them into the rebuilt structure.

Of the 25 float units that formed the pontoon, seven had to be replaced while 18 were able to be repaired, along with the transfer deck and jetty.

The final step in the process was lifting the 120 tonne linkspan back into place, a process that required the use of a 1,000 tonne capacity mobile crane. It was a massive exercise, but one that was deeply gratifying for the team who had overseen the process.

“After six months of work, it was very satisfying to see the bridge land in place. All the final pins slid in nicely. All the dimensions were right. It was very rewarding to see”, said Mr Traves.

The project was just the latest undertaken by Opus on behalf of ABP in a relationship of several years. But the scale of the project and its importance to the Port of Southampton mark it as a milestone.