High performance concrete with electric arc furnace slag as aggregate: Mechanical and durability properties Flora Faleschini a , M. Alejandro Fernández-Ruíz b , Mariano Angelo Zanini a , Katya Brunelli c , Carlo Pellegrino a,⇑ , Enrique Hernández-Montes b a Dept. of Civil, Environmental and Architectural Engineering, University of Padova, Via Marzolo 9, 35131 Padova, Italy b Dept. of Structural Mechanics, University of Granada (UGR), Campus Universitario de Fuentenueva, 18072 Granada, Spain c Dept. of Industrial Engineering, University of Padova, Via Marzolo 9, 35131 Padova, Italy highlights  The properties of conventional and EAF concretes are experimentally investigated.  High strength concrete with EAF slag can be produced with relatively high w/c.  The high density of EAF-HSC suggests a potential application as nuclear shielding.  Chloride ingress in the concrete matrix is evaluated through AgNO 3 spray tests.  EAF slag use in concrete promotes chlorides diffusion coefficient reduction. article info Article history: Received 11 June 2015 Received in revised form 8 August 2015 Accepted 12 October 2015 Keywords: EAF aggregate EAF concrete High performance concrete Durability Chloride diffusion Sustainability abstract This paper investigates the feasibility of using Black/Oxidizing Electric Arc Furnace slag (EAF) as coarse aggregate to produce High Performance Concrete (HPC). Various experimental mixes have been produced, fully replacing natural coarse aggregates with EAF slag, varying the cement dosages and the water/cement ratios, and they have been characterized through a mechanical and microstructural campaign. For some mixtures also durability has been evaluated, through a study about chloride ingress into concrete matrix. Results indicate that the use of EAF slag improves concrete strength and durability, reaching C60/75 strength class without using any mineral additions and maintaining relatively high water/cement ratio. Ó 2015 Elsevier Ltd. All rights reserved. 1. Introduction High Performance Concrete (HPC) is conventionally defined as a concrete with improved performances in terms of strength, work- ability and durability, which cannot be obtained with ordinary materials through routinely mixing, placing and curing operations [1]. Several Codes and Guidelines establish the design rules for the use of HPC in the construction of important civil engineering works, e.g. ACI-318 [1] and fib Bulletin 42 [2]. Generally HPC mixtures have higher quantities of binders than normal concrete, containing one or more supplementary materials (e.g. fly ash, silica fume and granulated blast furnace slag). They are characterized by low water/cement ratio (usually ranging from 0.2 to 0.4), and large doses of superplasticizer are used to achieve the required workability. The aggregates should be strong and durable, and compatible with the cement paste in terms of stiffness and strength. HPC has lead to important advances in the field of civil engineering, especially in the construction of high-rise buildings and long-span bridges. HPC performances allow engineers to reduce columns and beams size (increasing the available space and reducing the costs in formwork, reinforcing steel, etc.) and to extend structures’ service life. However, behind these advantages, progress of concrete industry has also determined a series of draw- backs, mainly related to the sustainability of this industrial sector. Concrete industry is in fact responsible of a relevant environmental footprint on our planet [3], with an increasing trend associated to the actual and future growth of developing economies, demanding http://dx.doi.org/10.1016/j.conbuildmat.2015.10.022 0950-0618/Ó 2015 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: carlo.pellegrino@unipd.it (C. Pellegrino). Construction and Building Materials 101 (2015) 113–121 Contents lists available at ScienceDirect Construction and Building Materials journal homepage: www.elsevier.com/locate/conbuildmat