Bond between steel and self-consolidating concrete: experiments and modelling

An experimental investigation was performed to study the bond between deformed bars and self-consolidating concrete (SCC) through pullout tests on short cylindrical anchorages. The specimens were cast with plain and fiber-reinforced (1% of steel fibers) SCC to evaluate the confinement given by fibers. In the case of plain concrete, tests were performed with and without lateral pressure. To assess size effects, three bar diameters were considered, and the geometry of the specimens was adopted to assume a constant ratio between the specimen diameter/bar diameter (= 9) and the bonded length/bar diameter (= 2). The results were analyzed by a limit analysis model to evaluate the ultimate bond capacity and concrete cover at which the splitting/pullout failure transition is observed. SCC exhibits higher bond strength and, compared to ordinary concrete, requires larger concrete cover to attain pullout failure.