Bond stress and behavior of interface between untreated aluminum alloy surface and concrete

Abstract

This paper explores the viability of using aluminum alloy (AA) plates as an externally bonded reinforcement (EBR) material that could overcome some of the shortcomings of the prevailing steel and FRP materials and provides new advantages. A total of 32 prisms with different concrete strengths have been prepared as single shear test specimens with AA plates bonded to the prisms at different lengths using epoxy adhesive. Single shear tests were conducted on the prism specimens until failure. Load-extension and load-strain values were recorded. Bond stress and bond slip values were calculated. Test results have shown that plain untreated AA surface is susceptible to premature debonding; however treating the AA surface, by roughening it, increases its bond strength and ultimate load capacity considerably. Generally, the ultimate load and maximum bond stress increased with the increase of the bonded length and concrete strength, on the average, for the AA roughened surface compared to the AA plain untreated surface, by up to 457%, 327%, respectively. It is also observed that the modes of failure were influenced by the changes in the bonded length, concrete strength and AA surface treatment.