Bond behavior of SRG-strengthened masonry units: Testing and numerical modeling

• Steel reinforced grout is used for strengthening bricks and bond behavior is investigated experimentally and numerically.
• Between mortar curing time and brick surface preparation, the latter influences remarkably the bond performance.
• The numerical model of the experiments is introduced comprising of bond–slip laws obtained through inverse fitting procedure.
• The effect of some design parameters on the overall bond behavior is studied using the validated numerical model.

Innovative materials such as steel reinforced grout (SRG) have shown superior behavior in terms of sustainability and compatibility comparing to their FRP counterparts for external strengthening of masonry structures. Considering the critical bond mechanisms at interfaces, this paper addresses an experimental and numerical investigation on bond in SRG-strengthened masonry by performing conventional single-lap shear bond tests revealing the importance of substrate preparation for application of SRG followed by a numerical model proposing suitable interfacial bond-slip laws. The numerical model, once validated against experimental results, is used to investigate further aspects of the bond behavior and the results are discussed.