Greystone Footbridge, Huyton
Overview
The design of the new footbridge would take the form of a symmetrical cable-stayed deck supported on the existing abutments and a newly constructed 7 metre high V-shaped concrete pier with a F5 concrete finish.
A steel pylon, “the Mast” approximately 23 metres tall would provide support to the stay cables.
The works included modifications to the existing abutments to accommodate the new steel plate deck and the installation of 20 metre long rotary bored piles to support the concrete pier.
Funded by Knowsley Council, the new bridge provides pedestrian and cyclist facilities which links the communities on either side of the motorway and is used by more than 400 people each day.
Key Challenges
The demolition and installation of the new footbridge required full weekend closures of the M62 motorway. The closures were immovable dates of fixed duration which occurred during international football breaks. This requirement was imposed to mitigate the impact on traffic generated by local football clubs, Liverpool and Everton. We ensured by pre-planning and collaborative working with all parties that these targets were achieved.
Another challenge faced by the team was working in the confined area of the central reservation to construct the pile cap and bespoke V shaped concrete pier.
The team were able to minimise the time required in the central reservation by procuring and adopting pre-formed bespoke shuttering which minimised on site erection time and also achieved the high specification concrete finish required by Knowsley Council.
Slew locks were fitted to heavy plant & machinery. Varioguard barriers were installed to confine the work area from being entered by motorway traffic and vice versa.
Added Value
The original design specification of the Mast, the main components were only available from Japan. We proposed an alternative bespoke Mast built from weathering steel that was made in Lancashire. This eliminated the significant programme risk associated with procuring large steel sections from Japan.
The replacement Greystone Footbridge was completed to budget and programme. It received a highly recommended award at the ICE NW Civil Engineering Awards.
Following the opening children from Malvern Primary school in Huyton, designed permanent pieces of art which were installed at the entrance to the bridge.