The most of the reinforced concrete frame structures of the European building stock have been built without attention to the seismic action or according to obsolete code. Before the 1970's, in all the Mediterranean area, plain rebars were employed for the longitudinal reinforcement of structural members. Due to their smooth surface, they are characterized by poor bond capacity; this results in a significant slip of the loaded bar from the surrounding concrete, which strongly increases the structural deformation capacity compared to modern ribbed rebars. Whereas the cyclic response of non-conforming reinforced concrete members and structural sub-assemblies is deeply investigated in literature, a scarce knowledge about anchored plain bar cyclic behaviour is noticed. In the recent years, detailed non-linear modelling of gravity load designed structures is widely used for the seismic vulnerability assessment; a deep investigation on full scale anchorage detailing is then fundamental for the correct modelling of such structures.. In the present paper an experimental investigation on different anchorage solution of plain rebar embedded in concrete is presented; straight, hook-ended and 45° bent rebar were analysed, monitoring their axial stress versus slip behaviour. A non-linear stress-slip behaviour was observed for all the anchorage solutions since the lower loading level. Stiffness degradation due to cyclic loading was observed; on the other hand, strength decay was visible only for straight anchorage length. Hook-end device and bar bent resulted effective in providing a good anchorage performance, on the other hand their response showed a progressive plasticization.

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The seismic vulnerability of rigidly attached masonry infills has been repeatedly highlighted through post-event surveys, experimental and numerical studies. Although many innovative solutions have been proposed, especially in the last decades, many aspects of these systems are object of ongoing or future studies. The ductile infills with sliding joints have been currently investigated by different researchers starting from experimental tests and using the test outcomes to calibrate and create finite element models with the aim to perform parametric analysis and define the local and global interaction with the structure. Moreover, the innovative infills with sliding joints have shown a completely different in-plane behavior with respect to the nonductile ones. Since the creation of the diagonal strut is avoided and the shear sliding mechanisms fostered in predefined sliding joints, the interaction between the masonry panel and the RC members represents novelty with respect to the "traditional" rigidly attached masonry solutions. Within the present paper the results of a numerical model calibrated according to inplane experimental tests are presented and the local interaction between the RC structural member and the innovative ductile infill with sliding joints is discussed. The study adopts a validated finite element model approach to an experimental campaign that has never been simulated through detailed FEMs and compares the numerical results with the experimental results related to the local effects.