Effect of curing condition on the mechanical properties of fly ash-based geopolymer concrete

Abstract

In the present study, the mechanical properties of geopolymer concrete (GPC) has been investigated. GPC represents a novel technology that is giving significant concern in industrial construction, especially in term of the current emphasis on sustainability. In this study, the NaOH and Na 2 SiO 3 solutions were used as an alkaline solution in all GPC mixes. Na 2 SiO 3 with 10 concentration of molarity, activator-to-FA ratio of 0.4, Na 2 SiO 3 /NaOH ratio of 1.75, and two curing regimes viz., ambient curing, and heat curing at 75 °C for 26 h were employed. The experimental results indicated that the geopolymer concrete strengths, modulus of elasticity, and other mechanical properties increased with heat curing as compared to ambient temperature curing. The elastic modulus of GPC was associated with the compressive strengths and similar to those of OPC concrete. Furthermore, the geopolymer concrete mixture requires proper mix proportion and temperaturecontrolled curing conditions to accomplish good results.

Systematic multiscale models to predict the compressive strength of fly ash-based geopolymer concrete at various mixture proportions and curing regimes

“…For each set, a single input variable was extracted at a time, and the effects of this variable were assessed by R 2 , RMSE, MAE, OBJ, and SI, which is illustrated in Table 2. According to the obtained results, the curing temperature is the most significant variable for the prediction of the compressive strength of FA-GPC for the whole LR, NLR, and MLR models, and this is match with a variety of researches that have been performed in the literature [21,27,31,40,81,87,92]. In this study, the curing temperature for the obtained data was ranged from 23 to 120˚C, thus increasing the curing temperature considerably increased the compressive strength of FA-GPC.…”

“…In the MLR model, like other developed models, the curing temperature, sodium silicate content, an alkaline liquid to the binder ratio were the most significant independent variables that affect on the compressive strength of the FA-GPC that is matched with the experimental works presented in the literature [21,23,25,27,28,31,38,40,55,81,87,92]. The relationships between the predicted and measured compressive strength of the training data set for FA-GPC was shown in Fig 19A . Further, same as the two previous models, this model was checked by two sets of data (testing and validating dataset) to show their efficiency for other data out of the model data (training data); the results show that this model can be used to predict the compressive strength of FA-GPC just by substitute the independent variables into the developed…”

Exploration of mechanical and durability characteristics of fly ash-GGBFS based green geopolymer concrete

“…The mix proportioning of GC was done according to previous reports by considering the density as 2400 kg/m 3 [6,7,10,17,[19][20][21][22]. The mix proportion details for GC M1 to M7 and control mix are presented in Table 3.…”

“…The industrial waste like fly ash, GGBFS, red mud, and silica fume are used as source materials in geopolymer concrete. The alkaline solution is prepared from potassium/sodiumbased soluble solutions [6][7][8][9][10][11][12][13]. The Alkaline-activation on these wastes like fly ash will be end product in the development of geopolymer Resin/Binder [14,15].…”

Structural performance of ambient‐cured reinforced geopolymer concrete beams with steel fibres

“…Regarding the geopolymer concrete production, many research works have been accomplished to understand the strength characteristics, mechanical properties, and fire resistance of GPC 38,39 . Most of these studies carried out to investigate the plain GPC without reinforcements 40 .…”