Scottish Trunk Road Network - South East Unit - Forth Road Bridge Side Tower Elastomeric Bearing Re

Descriptions

BEAR Scotland is seeking to appoint a suitably experienced SubContractor to undertake the Side Tower Elastomeric Bearing replacement scheme with an estimated value 1.0 million GBP.The Forth Road Bridge is a long span suspension bridge which spans over the Firth of Forth linking Edinburgh to Fife. The side Span is 408m long, Main Span is 1006m long. Side span composite deck segments are typically formed of an 18.1m long x 7.3m wide x 220mm deep reinforced concrete slab supported on 4no. mild steel stringer beams.The deck stringers are bolted onto the cross girders of the suspended truss at 9.1m centres. Each of the 4no. stringers of carriageway deck segments are supported on elastomeric bearings at the Side Tower (i.e. 1no bearing per stringer), 16no. bearings total. In addition, there are 2no. bearing supporting the footway (i.e 8 no. in total in 4 no. locations).The elastomeric bearings are nominally ‘free’: accommodating transverse and longitudinal movement (by shear deformation) and rotations about vertical, transverse and longitudinal axis. The Forth Road Bridge’s side spans’ elastomeric bearings at the Side Towers are over 54 years old, life expired and are in poor and degrading condition.The side tower elastomeric bearing replacement scheme includes for the installation of debris netting and a temporary working platforms. This shall enable the installation of temporary jacking brackets, jacking of the bridge deck and replacement of all elastomeric bearings as well as local refurbishment works. The works shall also require amendments to an existing impressed current cathodic protection system.