Open AccessSetting time and compression strength of low-calcium fly ash geopolymer paste with non-calcined red soil substitution in ambient curing
Author(s) -
Partogi H. Simatupang,
V. Nine,
A. E. Sinaga
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/669/1/012025
Subject(s) - geopolymer , fly ash , calcination , materials science , curing (chemistry) , sodium silicate , sodium hydroxide , compressive strength , hydroxide , composite material , chemistry , inorganic chemistry , organic chemistry , catalysis
This paper describes the research of the effects of non-calcined red soil substitution in low-calcium fly ash geopolymer paste in ambient curing. Mechanical characteristics observed were setting time and compression strength. The non-calcined red soil substitutions were varied i.e 0%, 5%, 25% and 50% of mass of fly ash. The alkaline solutions used were natrium silicate solution and natrium hydroxide solution 10 M with mass ratios 1:1 and 2:1. The results show that the higher the substitution of non-calcined red soil the longer the initial and final time setting of the geopolymer paste. Meanwhile, the higher the substitution of non-calcined red soil the lower the compression strength of the geopolymer paste. Furthermore, geopolymer paste with ratio of Na 2 SiO 3 / NaOH = 2.0 will has longer initial and final setting than geopolymer paste with ratio of Na 2 SiO 3 / NaOH = 1.0. Geopolymer paste with ratio of Na 2 SiO 3 / NaOH = 2.0 will has higher compression strength than geopolymer paste with ratio of Na 2 SiO 3 / NaOH = 1.0. All the relationships between the substitution of non-calcined red soil and setting time or compression strength of geopolymer paste can be drawn in exponential function.