The improvement of mechanical, physical and durability characteristics of volcanic tuff based geopolymer concrete by using nano silica, micro silica and Styrene-Butadiene Latex additives at different ratios

• Published in: Construction & building materials 2019-03, Vol.201, p.257-267
• Main Authors: Ekinci, Enes, Türkmen, İbrahim, Kantarci, Fatih, Karakoç, Mehmet Burhan
• Format: Article
• Language: English
• Subjects: Additives; Analysis; Butadiene; Chemical properties; Compressive strength; Concretes; Freeze-thaw; Geopolymer; Mechanical properties; Micro silica; Nano silica; Porosity; Silicon dioxide; Styrene-Butadiene Latex; Volcanic rocks
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2018.12.204

•Two different activation methods were used to produce geopolymer concrete.•Different additives were selected to improve properties of GPC samples.•Optimum additive ratios have been determined for each conducted test.•The activation method with NaOH led to superior mechanical properties.•In terms of FT resistance, the activation method of Na2SiO3 + NaOH was advantaged. This study aims to the improvement of volcanic tuff-based geopolymer concrete (GPC) with the addition of nano silica (NS), micro silica (MS) and Styrene-Butadiene Latex (SBL) at the different ratios. For this purpose, incorporating of volcanic tuff with NS (1, 2, 3%), MS (1, 3, 5%) and SBL (5, 10, 15%) was provided. GPC samples were produced with two different activation method (Na2SiO3 + NaOH and sole NaOH). 28-day compressive strength, freeze-thaw (FT) resistance, microstructure, water absorption, density, bulk density and apparent porosity values of volcanic tuff-based GPC samples were investigated. The results indicated that the compressive strength of NaOH-activated samples was much higher than similar ones activated with Na2SiO3 + NaOH. In both activation methods, the optimum NS and SBL ratios were determined as 2% and 5%, respectively. Also, the optimum additive of MS ratio was determined 5% and 3% for Na2SiO3 + NaOH and sole NaOH-activated samples, respectively. As well as the highest compressive strength losses as a result of 300 FT cycles were observed in pure samples for both activation methods, Na2SiO3 + NaOH-activated samples exhibited better resistance to FT effect than similar ones activated with sole NaOH.