QUICK THINKING by engineers on the Runcorn to Widnes Silver Jubilee Bridge last week rescued efforts to install a new expansion joint in the 40 year old bridge's concrete deck.
Engineers were forced to improvise when it was discovered that the final prefabricated 5.165m section of the Maurer D240B joint was 100mm too long to slot into the gap on the 13.5m wide concrete bridge deck.
To ensure that work was completed in the overnight lane closure engineers from joint supplier Maurer took to the steel segment with an angle grinder and shaved off the extra steel before slotting it into place.
The installation of the expansion joint is the main operation in a £2.1M upgrade being carried out by contractor Mowlem for Halton Borough Council.
Over 90,000 vehicles per day use the dual carriageway bridge, which carries traffic over the River Mersey between Runcorn and Widnes (NCE 3 June).
It has an asphalt coated concrete slab deck carriageway, which is supported by longitudinal and transverse steel beams. The whole deck is suspended from hangers attached to a pin jointed steel arch truss.
Main expansion joints sit 300m apart and the existing bespoke manganese bronze and rubber joints had not been replaced during the structure's 40 year life.
The new joints are made of steel beams spanning longitudinally between joist boxes cast into the deck concrete (see diagram). Work is scheduled to finish on 20 September.