Experimental response and fiber‐reinforced cement composites strengthening of real reinforced concrete columns with poor‐quality concrete

Abstract

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.

Quality assurance in reverse logistics supply chain of demolition waste: A systematic literature review

“…As shown in Table 3, experiment is the most popular research method used in refined articles. Since experiments provide scientific analysis to identify, reduce and correct quality issues with products (Del Vecchio et al, 2019), it is understandable why most of the research has used experiments as the research method in the current literature. Additionally, many studies have also employed case studies which help to understand the dynamics of the QA within the RLSC context (Eisenhardt and Graebner, 2007).…”

Assessment of analytical stress and strain at peak and at ultimate conditions for fiber‐reinforcement polymer‐confined reinforced concrete columns of rectangular sections under axial cyclic loading

“…The majority of the existing experimental and analytical investigations have been carried out to examine the stress–strain response of rectangular concrete columns with or without internal steel reinforcement confined with FRP, subjected to monotonic axial loading. Most of them have examined the experimental behavior and the analytical modeling of small‐scale concrete columns 2–10 and others have been focused on large‐scale specimens 4,11–15 …”

Bending Load-Carrying Capacity of Reinforced Concrete Beams Subjected to Premature Failure

“…As a result, accuracy of the ultimate load predicted by plastic analysis depends on the differences between the actual bending moment exhibited by each plastic hinge at the ultimate and the maximum bending moment that the plastic hinge can reach without being an element of the beam (i.e., peak of the moment–rotation relationship of the plastic hinge as an individual element) [11,12,13]. Accordingly, plastic analysis may overestimate the ultimate load; a lower ductility leads to greater overestimation [14,15,16].…”