Dunheved Bridge A30 Devon/Cornwall
Replacement of two bridge decks carrying the A30 over the River Tamar.
The scheme is an alternative solution proposed by Dean & Dyball to a refurbishment/cladding contract, to slow down the process of Alkali Silica Reaction (ASR) in the existing bridge decks, let by the Highways Agency.
Dean & Dyball initially won the compliant bid in open tender and concurrently offered this alternative, discussing construction methods, traffic management and costings. The primary innovation was to construct a temporary, third dual carriageway to the eastern side of the existing road. This enabled a traffic management plan that allowed traffic to remain dualled both ways for virtually all of the project. In addition to the improvements in traffic flows, the alternative proposal also provided the Highways Agency with a completely new bridge deck compared to a protected existing one and associated extended design life.
Our project management for the scheme concentrated on minimizing traffic disruption and putting in place all the arrangements necessary to complete the critical activities in sequence. All of the key milestones were achieved.
Our proposed solution enables most of the work to be carried out off-line and away from traffic, which negates one of the main risks to health and safety of the workforce.
All project parties were involved in a media day, prior to work on site, to explain the scheme and its potential impacts on the travelling public and near neighbours. The good relationship developed on site has enhanced Dean & Dyball’s capability to carry out major highway schemes.