VINCI Construction UK Site Team Reduces Installation of 663 Tonne Bridge Structure by Five Days

Hanger Lane is located on a busy section of the North Circular in North West London and crosses several railway lines. The Bridges Replacement project is vital to relieving congestion in the area.

Work on the South Bridge, which is being undertaken for Transport for London (TfL) and designed by Hyder, was recently installed using an alternative method developed by the Temporary Works team at VINCI Construction UK. Due to the constraints imposed by working in such restricted site conditions, the single span superstructure was launched over the rail lines using Self Propelled Modular Transporters (SPMTs). This avoided the need to close the North Circular for a total of five days to allow for crane erection using the traditional lifting method.

VINCI Construction UK specified that the 45 metre deck be constructed on site almost perpendicular to the launch direction. Two sets of SPMTs were positioned beneath the superstructure which included nose and tail temporary works designed by VINCI Construction UK. During a three hour rail possession, the SPMTs enabled the South Bridge to be lifted and rotated into its correct alignment and then launched over the railway lines. Lifting the bridge using the traditional method would have added five days to the installation for the rigging and de-rigging of a 1000 tonne crane.

Add to the 45 metre steel box girder bridge deck length the temporary nose and tail structures and the total length to be manoeuvred amounted to 77 metres. The total load launched was a massive 1084 tonnes which included 189 tonnes of reinforced concrete and 474 tonnes of steel used for the construction of the permanent deck.

Published: 12/07/2010