Open AccessThe Influence of Sodium Hydroxide Concentration on Physical Properties and Strength Development of High Calcium Fly Ash Based Geopolymer as Pavement Base Materials
Author(s) -
Liyana Ahmad Sofri,
Mohd Mustafa Al Bakri Abdullah,
Mohd Rosli Mohd Hasan,
Yue Huang
Publication year - 2020
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/864/1/012016
Subject(s) - fly ash , compressive strength , geopolymer , calcium hydroxide , sodium hydroxide , molar concentration , materials science , curing (chemistry) , composite material , chemical engineering , chemistry , organic chemistry , engineering
This paper deals with the development of high calcium fly ash based geopolymers. Geopolymer paste was prepared from fly ash alkaline activator solutions using various mix design including molarity of sodium hydroxide used (6-14M) with solid-to-liquid ratio (1.0-3.0) and the sample were curing at ambient temperature. In this paper, flow value, setting time and unconfined compressive strength of high calcium fly ash based geopolymer paste was carried out using flow table equipment, Vicat’s apparatus and compression testing machine to measure the properties caused by high calcium fly ash. It was found that solid to liquid ratio of 2.0 and NaOH molarity of 12M was the best mix design to be applied due to its maximum unconfined compressive strength achieved (up to 19MPa at 28 days) as well as its flow ability of the fresh paste which shown better result compared to other mix designs. High calcium was also found to result in higher strength.