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Poor‐quality concrete and a lack of transverse reinforcement commonly characterize the reinforced concrete (RC) structures built during the past century in the Mediterranean area. However, very few experiments have investigated the performance of structural members of that kind. Moreover, the design of repair and retrofit solutions using available techniques could be challenging due to the weakness of the concrete substrate. This paper reports on the experimental response and the repair and retrofit of existing RC columns with poor‐quality concrete. In particular, it presents and discusses the outcomes of three tests on two RC columns extracted from a real building that was severely damaged by the 2009 L'Aquila earthquake and was, as a result, demolished. The concrete compressive strengths resulting from in situ and laboratory material characterization tests are used to predict the axial strength of the sampled columns. An innovative application of fiber‐reinforced cement composites (FRCC) for the repair and retrofit of damaged columns is proposed and validated experimentally. The results reveal that this material is effective when it comes to recovering and improving the axial capacity of damaged RC members. Practical suggestions to account for the confinement effect of the thin FRCC jacketing in available analytical formulations are discussed. [ABSTRACT FROM AUTHOR]

This paper examines the problems of the seismic design of precast concrete structures as indicated by the effects of the L'Aquila earthquake of 2009. The behaviour of such structures on that occasion is analysed on the basis of detailed surveys performed on site on a relevant number of buildings just after the earthquake. Following this analysis, which points out the inadequacy of the cladding panel connections, the paper presents a systematic definition of the problem, examining the behaviour of the whole system of structure + panels. Proposals are made for the typology of one-storey buildings for industrial uses, some possible alternative solutions that ensure the stability of all the construction elements. Specific calculations for a typical precast building give the order of magnitude of the forces and/or displacements for which the connections are to be designed. [ABSTRACT FROM AUTHOR]