PROJECT PROFILE
	A31 Bridges, Farnham
In 2004 Structural Renovations carried out site investigation, testing and laboratory analysis of concrete samples to 3 bridges carrying the A31 over a bridleway and 2 sections of the River Wey at Farnham for Surrey County Council.  In addition a Specification and Bill of Quantities was prepared for the Client. The results concluded that all 3 bridges required concrete repair and protective coatings.  In addition 1 of the bridges required strengthening to meet current 40 tonne vehicle loading standards. The following year the Company was awarded the contract through the client’s term contactor, Ringway Highway Services, to carry out the full proposals including design and installation of carbon fibre composite plate bonding strengthening. Access to the soffits and walls to the bridge over the bridleway was a full birdcage scaffold maintaining access below for pedestrians and horses. Concrete repairs were carried out using polymer-modified hand placed repair mortars and flowable concrete supplied by Sika Ltd.  A range of coatings from clear anticarbonation to siloxane water repellent impregnation were applied as appropriate. Where the headroom permitted and after consultation with the Environment Agency, a low height scaffold founded on the riverbed was used to access the soffit to one of the bridges.	The second bridge had limited headroom and scaffold was not appropriate.
		The work here was carried out by operatives wearing waders and using small scaffold storage platforms to keep plant and materials free of the water.
	Strengthening to one of the bridges was carried out on the soffits using Sika CarboDur plates.  Design was carried out by Tony Gee & Partners on our behalf, working to the Client’s brief. Preparation of the soffit was carried out by light scabbling followed by cutting of the carbon fibre plates to length by guillotine. Epoxy resin was applied to both the prepared concrete surfaces and to the plates by drawing them through a gauge box.  The plates were then offered up by hand to the soffit and finished by a light roller extruding excess resin.
		This method of strengthening permitted traffic to continue to use the carriageways above giving minimal disruption to the road user.
	Project quantities 325m CarboDur S1012 cfrp plate
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