SYNOPSIS
Although resins have been used for repairing concrete for many years, there is still a lack of convincing data about their performance in this role. This is largely due to the absence of a suitable test for evaluating the repair techniques. Details are given of a test which realistically appraises the effectiveness of the injection of resin into cracks, the repair of damaged concrete with resin mortars and the use of resin primers with fresh concrete. The test piece is a rectangular prism with either a diagonal repaired crack or a scarf joint between the original concrete and the repair material. It is subjected to compressive test and compared directly with an undamaged concrete prism of similar dimensions. Thus the repair is subjected to a high degree of shear and is appraised in the same simple terms of cube or prism strength with which the engineer assesses the quality of his original concrete.
