Performance studies on quaternary blended Geopolymer concrete

Abstract

This experimental work studied the mix design, mechanical properties and durability properties for G40 and G60 Quaternary Blended Geopolymer Concrete. Quaternary means fourth in sequence; hence Geopolymer Concrete is composed of four binder materials: fly ash, ground granulated blast furnace slag (GGBS), rice husk ash, and Metakaolin. For the Binary mixed geopolymer mix, the ratio of flyash to ground granulated blast furnace slag was 70:30 for G40 grades and 60:40 for G60 rates. For the Ternary geopolymer mixture, Flyash: Ground granulated blast furnace slag: Metakaolinratio was taken as 50:30:20 and 40:40:20 for G40 and G60 grades, respectively. For quaternary blended geopolymer mix, Fly ash: Ground granulated blast furnace slag: Metakaolin: Ricehuskash ratio was taken as 30:30:20:20 and 20:40:20:20 for G40 and G60 grades, respectively. As an alkaline solution, sodium with silicate and hydroxide actuated the binder components. The ratio of alkaline activator (NaOH/Na2SiO3) was set at 2.5, and the concentration of NaOH was kept at eight molalities. The total ratio was calculated to be 5.18 for G40 and 4.18 for G60 grades. In this experimental investigation, flexural strength, split tensile strength tests, compressive strength (CS), Rapid Chloride Penetration Test (RCPT), sorptivity, and chloride permeability, were conducted. On geopolymer mortar, tests for Normal Consistency (mm), Initial and Final Setting Time (min), and CS(MPa) were undertaken. Results had shown that ternary blended geopolymer mortar had optimum values in CS. Quaternary composite geopolymer mortar had shown low CS. In quaternary blended geopolymer mortar, Initial and Final Setting Times were delayed. It had not performed well in the flexural strength test, compression strength test and split tensile strength test. It also showed low resistance for sorptivity, Rapid chloride permeability, and acid attack when compared with ternary and binary blended Geopolymer Concrete. Ternary mixed Geopolymer Concrete had optimal results in CS, flexural strength, and split tensile strength tests, as well as superior sorptivity, fast chloride permeability and acid attack resistance.