Concrete and geopolymer materials paper
Myadaraboina, H, Solikin, M, Patnaikuni, I & Setunge, S 2014, 'Development of high volume fly ash concrete using ultra-fine fly ash', in ST Smith (ed.), 23rd Australasian Conference on the Mechanics of Structures and Materials (ACMSM23), vol. I, Byron Bay, NSW, 9-12 December, Southern Cross University, Lismore, NSW, pp. 65-70. ISBN: 9780994152008.
Given one ton of cement is producing nearly one ton of CO2, there is need to reduce the cement production worldwide to make the concrete sustainable. On the other hand, fly ash (FA) production levels worldwide have increased. Therefore, there is a need to examine the issue of increasing FA levels in concrete. High Volume Fly Ash Concrete (HVFAC), which is defined as the FA replacements above 50 % partly addresses this issue. The replacements can be up to 85%. But, unlike geopolymer concrete with 100% fly ash, HVFAC does not require heat curing which is an advantage over geopolymer concrete to be accepted by the construction industry. This research is aimed to produce high volume high performance fly ash concrete by reducing the drawback of low early strength of HVFAC. To achieve this, few key factors are considered in mix design and investigated studying microstructure of HVFAC. The factors being the w/b ratio, fineness of fly ash added, type of mixing water and dosage of super plasticizer. The experimental results of 50% replacement of cement with ultra-fine fly ash, raw fly ash with tap water and lime water as mixing water are presented in this paper.