As part of a refurbishment project of the new East West Road Link in Lincoln, an existing road bridge over the Sincil Dyke Drain was to be removed to make for a new bridge.
The bridge was a constructed from a reinforced bridge deck supported by 900 mm depth steel and plate girder beams. The overall length of the bridge was approximately 15m long and a width ranging from 6 to 9 metres, the weight of the structure was approximately 90 tonnes.
Gnat Uk Ltd were consulted to formulate a method taking into consideration the sensitivity of the waterway and no debris was permitted to fall into the water.
Gnat were sub contracted to carry out all the diamond core drilling and saw cutting of the 280mm slab.
150mm core holes were drilled through the slab and the predetermined locations to allow the lifting chains to pass through. Gnat operatives then saw cut the bridge into sections to release and enable the crane to lift and set down in the designated area. This process was repeated until all sections were successfully released and lifted.
A crane with a 220 tonne capacity was to be used to lift the sections from the abutment walls, due to the lifting radius the section were to be cut into 6 sections and pontoon was set up below the bridge to allow access to the underside to cut the steel beam and sling the lifting chains.
Following on from the bridge demolition the main contractor, Balfour Beatty then constructed the new bridge.
Removal of last sections of the bridge deck