Abstract
A structural appraisal of Jordangate MSCP in Macclesfield, built in the 1 980s, identified chloride penetration within the concrete and recommended treatment using cathodic protection to control the corrosion of the structural steel, together with concrete repairs and waterproofing of the car decks and other associated works. The original worst-case scenario estimates were put forward for budgetary purposes, with more accurate costs dependant on the outcome of further testing and appraisals. Following budget approval, a review of the original structural appraisal report advised that as the effects of chloride penetration had not yet materialized, the use of cathodic protection was not considered to be essential at this stage. The recommendation was that concrete repairs be undertaken and waterproofing be applied to the concrete decks to eliminate water penetration, thereby reducing the risk of chloride attack, followed up by a regular monitoring regime to ensure that conditions had not deteriorated. A number of products from BASF Construction Chemicals were used by Concrete Repairs Limited in carrying out the refurbishment. Numerous deck repairs were needed prior to deck covering and a special CONIDECK? deck membrane strip system tackled the cracking along the joints of the block and beam construction.