Cantilever solution

Carrying Out A Major Refurbishment of a bridge on a busy road with minimal traffic disruption is not an easy challenge. Nonetheless, it is one that contractor Dean & Dyball is undertaking on the Dunheved Bridge which carries the A30 over the River Tamar near Launceston in Cornwall, UK.

The existing deck is suffering from alkali silica reaction and Dean & Dyball has been charged with the UK£ 3,8 million (€ 5,6 million) job to replace the deck with composite reinforced concrete and steel structure.

Complete closure of the road during the work was not an option, according to project's client the Highways Agency, so the contractor is using a falsework system designed by SGB to construct the new deck alongside the existing one. Once work on the new deck is complete, the existing one will be demolished and the new one will be slid into position during an overnight closure.

SGB's solution for the project also uses the company's Multiform Bridge Parapet bracket to cantilever the formwork for the new bridge parapets. According to SGB, the cantilever system uses less equipment that a conventional under-slung approach and improve on site safety.

Construction on site is currently progressing well and on schedule to be completed in March next year.