A Mix Design Procedure for Alkali‐Activated High‐Calcium Fly Ash Concrete Cured at Ambient Temperature

Abstract

is research focuses on developing a mix design methodology for alkali-activated high-calcium fly ash concrete (AAHFAC). High-calcium fly ash (FA) from the Mae Moh power plant in northern ailand was used as a starting material. Sodium hydroxide and sodium silicate were used as alkaline activator solutions (AAS). Many parameters, namely, NaOH concentration, alkaline activator solution-to-fly ash (AAS/FA) ratio, and coarse aggregate size, were investigated. e 28-day compressive strength was tested to validate the mix design proposed. e mix design methodology of the proposed AAHFAC mixes was given step by step, and it was modified from ACI standards. Test results showed that the 28-day compressive strength of 15-35 MPa was obtained. After modifying mix design of the AAHFAC mixes by updating the AAS/FA ratio from laboratory experiments, it was found that they met the strength requirement.

Survey of Mechanical Properties of Geopolymer Concrete: A Comprehensive Review and Data Analysis

“…Behavior of GPC with nanomaterials was investigated by Phoo-ngernkham et al [ 14 ]. Pozzolanic materials used for GPC mixes were mostly class F fly ash; however, class C fly ash [ 22 ], Phoo-ngernkham et al [ 23 ], natural Pozzolan [ 24 ], ground granulated blast furnace slag (GGBS) [ 25 , 26 ], metakaolin [ 27 , 28 ], rice husk ash [ 29 ], a mixture of two or more Pozzolanic materials [ 30 , 31 , 32 ], and ceramic dust waste [ 33 ] were also examined. Some special ashes or compounds were used by some investigators such as palm oil fuel ash (POFA) [ 34 ], waste bottle glass (WBG) [ 35 ], and sugarcane bagasse ash (SCBA) [ 36 , 37 ].…”

A Review of Recent Developments and Advances in Eco-Friendly Geopolymer Concrete

“…Moreover, the strength-based mix design was proposed based on ACI standard (ACI 211.4R-93) [82] with some modifications. This procedure depends on activator to binder ratio, activator concentration, and aggregate gradation [83], as given in Figure 4. modifications.…”

“…modifications. This procedure depends on activator to binder ratio, activator concentration, and aggregate gradation [83], as given in Figure 4.…”

“…According to Mehta and Siddique [111], the workability depends on the fineness of the aluminosilicate particle and SiO 2 /Al 2 O 3 ratio [111] present in GPC. The more value of fineness, the higher the slump value of GPC and vice versa [83].…”

Effect of Curing Conditions on Microstructure and Pore-Structure of Brown Coal Fly Ash Geopolymers

“…Chindaprasirt al. 2013 [25] produced geopolymer concrete using high calcium, Class C fluidized bed combustion fly ash, cured at 60 • C for 24 h. Phoo-Ngernkham et al [26] showed that the 28-day compressive strength of 15-35 MPa can be obtained using alkali-activated high calcium fly ash concrete cured at ambient temperature (23 ± 1 • C). Further, Diaz et al [27] used three high calcium, Class C fly ashes obtained from power plants around the United States in order to produce geopolymer concrete while it cured for 3 days at 60 • C. Palomo et al [28] produced geopolymer concrete using law calcium Class F fly ashes cured at 65 • C and 85 • C for 24 h, and showed the importance of heat curing, where a significant increase in strength was observed at 85 • C as compared to 65 • C. Moreover, Bakharev [17] developed geopolymer concrete using two Australian low calcium Class F fly ashes cured at 100 • C for 24 h. In the case of brown coal fly ash, Dirgantara et al [15] observed the alkali activation of brown coal fly ash obtained from La Trobe Valley, Victoria, Australia required heat curing of 120 • C for 24 h to optimize the strength development and that the application of lower curing temperatures gave significantly lower compressive strengths.…”