Performance of Sustainable Fly Ash and Slag Cement Mortars Exposed to Simulated and Real In Situ Mediterranean Conditions along 90 Warm Season Days

• Published in: Materials Vol. 10; no. 11; p. 1254
• Main Authors: Ortega, José Marcos, Esteban, María Dolores, Sánchez, Isidro, Climent, Miguel Ángel
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 31-10-2017; MDPI
• Subjects: Blast furnace practice; Blast furnace slags; Carbon dioxide; Cement; Clinker; Exposure; Fly ash; Granulation; Intrusion; Laboratories; Microstructure; Mortars (material); Porosity; Portland cements; Simulation; Suction; relative humidity; durability; temperature; fly ash; non-optimum laboratory condition; ground granulated blast-furnace slag; Mediterranean climate environment; real condition exposure; ordinary Portland cement; sustainability
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma10111254

Nowadays, cement manufacture is one of the most polluting worldwide industrial sectors. In order to reduce its CO₂ emissions, the clinker replacement by ground granulated blast-furnace slag and fly ash is becoming increasingly common. Both additions are well-studied when the hardening conditions of cementitious materials are optimum. Therefore, the main objective of this research was to study the short-term effects of exposure, to both laboratory simulated and real in situ Mediterranean climate environments, on the microstructure and durability-related properties of mortars made using commercial slag and fly ash cements, as well as ordinary Portland cement. The real in situ condition consisted of placing the samples at approximately 100 m away from the Mediterranean Sea. The microstructure was analysed using mercury intrusion porosimetry. The effective porosity, the capillary suction coefficient and the non-steady state chloride migration coefficient were also studied. In view of the results obtained, the non-optimum laboratory simulated Mediterranean environment was a good approach to the real in situ one. Finally, mortars prepared using sustainable cements with slag and fly ash exposed to both Mediterranean climate environments, showed adequate service properties in the short-term (90 days), similar to or even better than those in mortars made with ordinary Portland cement.