Bonding Systems for Concrete Repair — An Assessment of Commonly Used Materials

Commercially available aqueous polymer dispersions of various types are compared with respect to their bonding properties when used to adhere repair mortars to cementitious substrates. Polymer dispersions tested include a number of acrylates and styrene-acrylates, a styrene butadiene, a vinyl acetate, an acrylate versatate and a vinyl acetate acrylate versatate. A composite bonding aid, an epoxy bonding system and the use of cement and polymer/cement slurries are also examined. Three different test methods are used to measure bond and a simple comparative test has been developed to monitor ‘grab’. The merits of these tests are discussed. The best all round performance including tolerance to site use has been found to be given by an acrylate dispersion.