Construction and demolition waste as an addition in new cements. effect on carbonation

Author(s): Caesar Medina Martinez, Isabel Fuencisla Sáez del Bosque, Eloy Asensio de Lucas, Moisés Frías Rojas, María Isabel Sánchez de Rojas Gómez
Paper category: Proceedings
Book title: Proceedings of the International Conference on Sustainable Materials Systems and Structures (SMSS2019) Durability, Monitoring and Repair of Structures
Editor(s): Ana Baričević, Marija Jelčić Rukavina, Domagoj Damjanović, Maurizio Guadagnini
ISBN: 978-2-35158-217-6
e-ISBN: 978-2-35158-218-3
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 381-388
Total Pages: 813
Language: English

Abstract: In recent decades the cement industry has sought new additions to reduce the clinker content and CO2 emissions in cement manufacture. That pursuit has roused growing interest in the international scientific community around how the durability of these new cements may be affected by the use of industrial waste from steel mills, construction and demolition or others as supplementary cementitious materials. Particular attention has focused on carbonation, which induces concrete reinforcement corrosion. That type of decay merits attention, for approximately two-thirds of the existing concrete structures are exposed to environments where carbonation is a real risk. This study analysed the viability of designing new eco-efficient cements with 25 wt% construction and demolition waste from a dual perspective: their mechanical performance and their durability when exposed to natural carbonation. The research consisted in testing the compressive and flexural strength in 28 day 4x4x16 cm3 mortar specimens and the same parameters after 3 months and 6 months of natural carbonation, as described in Spanish standard UNE 83993-1. The findings showed that irrespective of the type of waste, the specimens complied with the mechanical requirements laid down in European standard EN 197-1. Carbonation was observed to penetrate the additioned specimens more deeply than the control, as reported for cement bearing standardised
additions such as blast furnace slag and fly ash.

: Online publication :2019
Publication type : full_text
Public price (Euros) : 00