Effects of compressive strength, autogenous shrinkage, and testing methods on bond behavior of high-early- strength engineered cementitious composites

An experimental study was undertaken to assess the bond characteristics of high-early-strength engineered cementitious composites (HES-ECC) with characteristics of high ductility and low early-Age shrinkage. For comparison purposes, a mixture of repair material (REP), which is commercially available and extensively used for fast and durable repair of infrastructures, was used to compare the bonding performance. For the evaluation of bond characteristics, slant shear and tensile pulloff tests were performed. In this study, the influence of compressive strength and autogenous shrinkage on individual bond strength results is also discussed, along with the basic mechanical properties of the proposed materials. Experimental results indicate that the influence of compressive strength and autogenous shrinkage on bond strength results varies significantly depending on the test method. It was also shown that the use of HES-ECC mixtures significantly improves the bond characteristics of a repair assembly in comparison to REP. Enhanced bond performance of HES-ECC mixtures over REP is more evident in the case of direct pulloff tests than in slant shear tests, both in terms of bond strength results and failure type.