815 ACI Structural Journal/November-December 2015 ACI STRUCTURAL JOURNAL TECHNICAL PAPER A study regarding the structural behavior of four three-dimensional, full-scale, recycled-aggregate concrete frame structures was carried out. This paper describes the fnal tests, which consisted of destructive horizontal tests, with incremental monotonic loading, in accordance with a pushover analysis. The test structures had a varying content of coarse recycled aggregates (0%, 25%, 100%, and 100% with high-range water-reducing admixture—in overall volume of coarse aggregates). These aggregates were gener- ated from the concrete precasting industry—that is, they are high quality and their negative effect on the recycled aggregate concrete mixtures was not expected to be signifcant. The four structures had the same geometry and reinforcement layout, and their design complied with Eurocode 2, Eurocode 7, and Eurocode 8. All the structures exhibited a ductile behavior, and their behavior was not signifcantly affected by the incorporation of recycled aggregates. There were also no differences in the cracking response. To the authors’ best knowledge, this is the frst time that such experiments were made in full-scale recycled-aggregate concrete structures. Keywords: full-scale models; pushover; recycled-aggregate concrete; structural behavior; three-dimensional frame. INTRODUCTION AND RESEARCH SIGNIFICANCE The use of recycled aggregates (RA) in concrete is a step toward sustainability, enabling a reduction of the use of natural resources and of the waste produced. However, the structural behavior of structures made with RA has not been fully studied, especially concerning their seismic response. To study the applicability of this kind of material by the construction industry, this experiment aims at assessing whether the performance of RA concrete (RAC) structures, when subjected to seismic actions, follows the assumptions made when designing conventional reinforced concrete structures. Not only is the mechanical (linear and nonlinear) behavior of RAC structures evaluated, but also the use of the calcu- lation methods employed in common concrete structures in this kind of material. This evaluation is made by the study of quantitative and qualitative parameters measured stage- by-stage during a monotonic destructive load application in compliance with the pushover analysis defnition in Euro- code 8. Additionally, because no full-scale studies regarding the behavior of RAC structures have been made, the evaluation of possible size effects is a necessary step toward the use of RAC (for instance, the ductility of a scaled-down specimen can overestimate the actual ductility of a structure, as argued by Bažant [1999]). Other innovative aspects of this experiment are the use of RA from the precasting industry (thus, high quality is expected) and that, contrary to most studies, these structures were executed in a common construction environment, with choices made to comply with such working conditions (such as a simpler aggregate grading). Therefore, it can be stated that this study aims at replicating the performance of RAC structures as if they were built for common construction purposes, and not for research purposes. The experiment also aimed at raising awareness and trust in the applicability of RA in concrete structures, providing an eco-friendly solution to precast rejects by confrming that the use of RA allows building reinforced concrete structures with an adequate seismic behavior. Only the use of the coarse fraction of the recycled aggre- gates was considered because the fne fraction tends to have a higher percentage of attached mortar, thus resulting in a larger loss of durability and mechanical properties (González- Fonteboa and Martínez-Abella 2007; Sato et al. 2007). LITERATURE REVIEW General introduction The main difference between conventional concrete (CC) and RAC is that RAC contains RAs, which are made of natural stone aggregates and mortar attached to them. The presence of this mortar has a series of implications on the behavior of RAC, mostly due to the higher porosity and permeability of this material: RAC tend to have higher water absorption; lower durability performance (Kwan et al. 2012; Olorunsogo and Padayachee 2002), which can be mitigated with fy ash (Kou et al. 2012); lower workability; and, most probably, lower mechanical performance, refected mainly on a decrease of the Young’s modulus E (Fonseca et al. 2011; Kou et al. 2012). Studies regarding shrinkage and creep show that these properties tend to increase with the use of RA (Ferreira et al. 2011; Poon et al. 2002). Despite in some cases deteriorating the properties of concrete, the use of RA is not barred by this effect. Further- more, the studies that compare RAC properties with regula- tions and engineering codes (Gonçalves and de Brito 2010) are almost unanimous in concluding their compliance. Title No. 112-S67 Destructive Horizontal Load Tests of Full-Scale Recycled- Aggregate Concrete Structures by João Pacheco, Jorge de Brito, João Ferreira, and Diogo Soares ACI Structural Journal, V. 112, No. 6, November-December 2015. MS No. S-2014-146.R4, doi: 10.14359/51687800, received November 24, 2014, and reviewed under Institute publication policies. Copyright © 2015, American Concrete Institute. All rights reserved, including the making of copies unless permission is obtained from the copyright proprietors. Pertinent discussion including author’s closure, if any, will be published ten months from this journal’s date if the discussion is received within four months of the paper’s print publication.