Novel coal bottom ash waste composites for sustainable construction Ertug Aydin European University of Lefke, Lefke, North Cyprus, via Mersin 10, Turkey highlights  Novel materials can be manufactured from coal bottom ash wastes.  Sustainable construction is possible for cement paste composites.  Alternative materials can be produced for control low-strength applications.  Developing sustainability strategies in building construction to reduce CO 2 emissions is mandatory.  Comprehensive literature review on the topic is provided. article info Article history: Received 22 March 2016 Received in revised form 27 July 2016 Accepted 29 July 2016 Keywords: Bottom ash Paste Sustainable construction Composite Sulfate Lightweight abstract The construction industry generates large amounts of greenhouse gases, which negatively impact the environment and society. International actions have increased to reduce the carbon footprint of this industry. A way to achieve this target is by promoting a sustainable construction industry e.g., by recy- cling bottom ash waste for producing ecological products. This paper examines the potential use of coal bottom ash residue, obtained from a brick-producing factory, in cement pastes. The physical, mechanical, and sodium sulfate test results revealed the lightweight nature of the prepared composites, which are suitable for use in brick, tile, paving stone, and controlled low-strength applications. Ó 2016 Elsevier Ltd. All rights reserved. 1. Introduction Portland cement (PC) is widely used in the construction indus- try. Specifically, PC is the most widely used component in concrete [1], and its use accounts for 90% of the world’s carbon dioxide (CO 2 ) emissions [2], which are known to have detrimental impacts on the environment and society. In most parts of the world, the replacement of clinker with supplementary cementitious materials (SCMs) is the conventional way to reduce CO 2 emissions, provided the SCM is a low-carbon material (e.g., fly ash or bottom ash) [3,4]. There is a growing interest in a sustainably built environment, and green technologies are gaining worldwide attention. However, such non-traditional technologies typically require more invest- ment to achieve high efficiencies when compared with established traditional technologies [5–8]. To this effect, Wu et al. suggested introducing a carbon-labeling scheme to encourage benchmarking and to develop sustainable building construction [6]. Sustainability is popular in the construction industry when metropolitan areas are considered. Building sustainability became popular in the 1990s and its assessment criteria have been used to incorporate sustainability into the building industry worldwide [9]. As the construction industry is developing, so is the demand for sustainable materials. Thus, considering the need for changes in performance, building designers are working toward including new procedures in design processes by considering environmental issues [10]. The global need for construction materials is estimated to be 13,000 ton/year for a sustainable construction industry; and 80% of those materials constitutes of limestone, clay-based materi- als, and sand [11]. The American Coal Ash Association has supported the use of coal combustion products (CCPs) to help achieve environmental friendly, technically sound, commercial, and sustainable building construction since 1968 [12]. CCPs have been used in diverse appli- cations for over 2000 years. The Resource Conservation and Recov- ery Act is the principal governing statute for the management and use of CCPs. Furthermore, the use of CCPs has been assessed by the U.S. Environmental Protection Agency; the evaluations revealed that CCPs do not present a significant risk to the environment [13]. As an example of a CCP, bottom ash (BA) consists of coarse gran- ular particles, which can be collected at the base of boilers. BA is http://dx.doi.org/10.1016/j.conbuildmat.2016.07.142 0950-0618/Ó 2016 Elsevier Ltd. All rights reserved. E-mail addresses: eraydin@eul.edu.tr, eaertugaydin@gmail.com Construction and Building Materials 124 (2016) 582–588 Contents lists available at ScienceDirect Construction and Building Materials journal homepage: www.elsevier.com/locate/conbuildmat