Evaluating the bond strength of repair materials under harsh environmental loading

When considering aging infrastructure, repair paths are often taken as a cheaper solution to extend the life the structure. Repair materials are selected for their sustained capacity to withstand the load. This study evaluated the durability of repair materials, based on the principles of engineered cementitious composites against traditional concrete mixes. The durability of the repair materials was evaluated through a comprehensive testing regime which evaluated the performance of the materials in isolation as well as in combination with a prescribed substrate. While the SCM based repair mixes withstood durability tests comparability and did outperform the reference concrete, the improvement wasn’t significant enough to justify the costs associated. The slant shear method may not be the optimal way to measure bond strength as a valid result is greatly dependent on the ratio of bond to compressive strength for the mix in question. Additional testing is recommended.