Steel–concrete bond in lightweight fiber reinforced concrete under monotonic and cyclic actions

Experimental results of the local bond stress–slip relationship of reinforcing bars embedded in lightweight fiber reinforced concrete with expanded clay aggregates are presented. The effect of the following parameters were investigated: — dimension of specimens; — anchorage length; — percentages of hooked steel fibers; — geometrical ratio of transverse reinforcement; — confinement external transverse pressure. Prismatic specimens with deformed steel bars embedded for a fixed length equal to five and eight equivalent diameters were tested under both monotonic and cyclic reversal imposed displacements at the tip of the bars, in controlled displacement tests. The influence of the above mentioned parameters was investigated, and the effects in terms of strength and ductility of the confinement due to transverse steel, to the fibers or to the pressure applied externally are shown.