A406 Superscheme

Sector: Specialist Highways
Client: TFL
Main Contractor: Conway AECOM
Project: A406 Superscheme
Works: Replacement of RC retaining wall, refurbishment of Neasden Iron bridge deck and parapet foundations
Duration: 2 months
Value: £625,000

The Neasden Superscheme was divided into three phases. 1) Dog Lane retaining wall replacement – remove acoustic barrier and existing VRS, saw cut and breakout of the carriageway, partial demolition of the existing RC retaining wall, repair to the construction joint, reinstatement of a new RC retaining wall. 2) Neasden Iron Bridge refurbishment – remove existing steel parapet, saw cut and breakout VRS foundations, breakout and remove existing bridge deck mass fill, refurbish bearing shelf access chambers, reinstall new RC VRS foundations with water main carrier, reinstall new deck mass fill to revised levels, breakout and replace RC abutment retaining wall and expansion joint 3) Dog Lane Arches – breakout existing VRS foundations, replace with new RC foundations including water main carrier, remediate back-of-arch drainage, repoint and repair cracks to brick parapet.

Other works included attendance to Thames Water for breakout and excavation, light column bases, duct installation and reinstatement of paving flags.