MATERIALS INTERNATIONAL | https://materials.international | 236 Cite This Article: Çınar, E.; Dündar, B.; Uygunoğlu, T. Investigation on High Temperature Effect of Recycled Concrete Aggregate on Mortars. Mat Int 2020, 2, 0236-0241. https://doi.org/10.33263/Materials22.236241 Investigation on High-Temperature Effect of Recycled Concrete Aggregate on Mortars Emriye Çınar 1 , Behçet Dündar 1 , Tayfun Uygunoğlu 2, * 1 Osmaniye Korkut Ata University, Faculty of Engineering, Department of Civil Engineering, Osmaniye, Turkey; emriyecinar@osmaniye.edu.tr; behcetdundar@osmaniye.edu.tr 3 Afyon Kocatepe University, Faculty of Engineering, Department of Civil Engineering, Afyonkarahisar, Turkey; uygunoglu@aku.edu.tr * Correspondence: uygunoglu@aku.edu.tr; Scopus ID: 14627796200 Abstract: In this study, the use of Recycled Concrete Aggregate (RCA) in mortar samples and their effects on mortars under high temperature were investigated. Mortar samples were produced in the dimensions of 40x40x160 mm. GDA, which has been converted into fine aggregate, has been replaced with 25%, 50% 75% and 100% of the sand used in mortar production. Mortar samples were exposed to 200, 400, 600, and 800 ⁰C after 28 days of standard curing. After the applied temperature, ultrasound transition speed, weight losses, flexural and compressive strengths were determined. With the increase of RCA, there was a decrease in the physical and mechanical properties of the mortars. Along with the increase in temperature, ultrasonic pulse velocity, compressive, and bending strengths were also decreased. Keywords: Mortar; High temperature; Recycled Concrete Aggregate; Sustainability. © 2020 by the authors. This article is an open-access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). 1. Introduction The inclusion of by-products used in place of natural aggregates in concrete is a valid strategy to minimize impacts in different industrial processes due to increased waste generation [1]. Replacing aggregates with various recycled materials has led to significant advances in the construction industry, reducing the need for new natural aggregates. Materials used as an alternative to natural aggregate include recycled concrete, recycled glass, scrap tires, plastics, and by-products of other industries [2-3]. Construction wastes, which is called as rubble, can occur with intentional destruction for reasons such as remodeling and repair, as well as destruction as a result of earthquake-like natural disasters [4]. When concrete structures are demolished or renewed, recycling of concrete is an increasingly common method of disposing rubble [5-6]. Recycling of these wastes has become a more attractive option with the recycling process due to the increase of environmental awareness because of the insufficiency in the landfills and destruction of fertile fields, which were previously carried to waste storage areas [7]. In order to produce recycled aggregates instead of natural aggregates, it is a practical solution that mechanically crush of concrete and reduce it to aggregate sizes [8-9]. A Volume 2, Issue 2, Pages 0236-0241 2020 Article ISSN: 2668-5728 https://materials.international https://doi.org/10.33263/Materials22.236241 Received: 10.05.2020 Accepted: 22.05.2020 Published: 25.05.2020