On the Development of Fly Ash-Based Geopolymer Concrete

Hardjito, Djwantoro; Wallah, Steenie E.; Sumajouw, D. M. J.; Rangan, B. Vijaya

doi:10.14359/13485

Cited by 177 publications

(56 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Moreover, in order to gain a 30-min initial working time, borax (11648, Riedel-de Haen) was ground by Retsch RS200 for 30 s and then used as a retarder in mortar; the borax content was calculated based on the percentage of geopolymer solid (see the details in Ref. [42]). The details of mixture are in Table 3.…”

Section: Alkali-activated Ladle Slagmentioning

confidence: 99%

See 1 more Smart Citation

High performance cementitious composite from alkali-activated ladle slag reinforced with polypropylene fibers

Nguyen

Carvelli

Adesanya

et al. 2018

Cement and Concrete Composites

View full text Add to dashboard Cite

A B S T R A C TAlkali-activated ladle slag (AALS) is a promising cementitious material with environmental benefits. However, the brittleness of material has been limiting the use in construction. Therefore, in this experimental investigation, different polypropylene (PP) fibers were employed as a short randomly reinforcement in cementitious matrix in order to improve mechanical performance of the AALS composites.The study reveals that the AALS composite could gain very high ductility with an appropriate fibrous reinforcement. Fracture energy and fracture toughness of PP fiber reinforced AALS mortars increased by approximately 150 and 7.6 times, respectively, compared to the unreinforced material. Additionally, the flexural strength of the composite increased by roughly 300%. Pseudo strain hardening (PSH) behavior was observed along with multiple cracks under uniaxial tensile test. Scanning electron microscope (SEM) images confirmed the local fiber bridging effect, which resulted in the high mechanical performance of the PP-reinforced AALS.

show abstract

Section: Alkali-activated Ladle Slagmentioning

confidence: 99%

“…Fracture energy was estimated by: Table 3 Mix proportions of the AALS reinforced with PP fiber (*Borax content was calculated as percentage of geopolymer solid, see details in Refs. [38,42] …”

Section: Fracture Toughnessmentioning

confidence: 99%

High performance cementitious composite from alkali-activated ladle slag reinforced with polypropylene fibers

Nguyen

Carvelli

Adesanya

et al. 2018

Cement and Concrete Composites

View full text Add to dashboard Cite

show abstract

“…Geopolymer materials are a novel construction technology that could be employed for green construction purposes [7][8][9]. There are two significant ingredients of geopolymer concrete, namely the source material with rich Alumina-Silica content such as fly ash (FA), metakaolin or GGBFS), and alkali activator, which consists of sodium silicate and sodium hydroxide solutions [10][11][12][13]. The raw material which is rich in Aluminium (Al) and silica (Si) such as GGBFS, fly ash, or metakaolin reacts with an alkaline solution to produce alumina silicate gel [14][15][16].…”

Section: Introductionmentioning

confidence: 99%

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

2019

View full text Add to dashboard Cite

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.

show abstract

“…The alkali content (in terms of Na 2 O or K 2 O) and modulus of the four curing mediums used in this study are listed in Table 2. It should be noted that the selection of the type of NaOH and KOH solutions and Na 2 SiO 3 and K 2 SiO 3 solutions and the specific formulations of the curing mediums used in this study were based on the numerous research studies (e.g., Hardjito et al, 2004;Wallah and Rangan, 2006;Kong and Sanjayan, 2010;Nematollahi et al, 2014Nematollahi et al, , 2017a conducted by the authors and other researchers around the world on the production of geopolymer paste, mortar and concrete for "civil engineering" applications.…”

Section: Curing Mediumsmentioning

confidence: 99%

Post-processing Methods to Improve Strength of Particle-Bed 3D Printed Geopolymer for Digital Construction Applications

Nematollahi

Xia

2019

Front. Mater.

View full text Add to dashboard Cite

The strength of powder-based 3D printed geopolymer samples immediately after the de-powdering process ("green" strength) is inherently very low. Therefore, different post-processing techniques have been explored in the previous study of the authors to enhance the "green" strength of the printed geopolymer. The highest strength of around 30 MPa was achieved for the printed slag-based geopolymer sample cured in an alkaline solution for 7 days at 60 • C. Although this strength is sufficient for a wide range of construction applications, the necessity for the heat curing procedure, which requires a significant amount of energy, can compromise the sustainability credentials of the developed powder-based 3D printed geopolymer and limit its commercial viability and large-scale applications in the construction industry. To tackle this issue, this study aims to develop a new post-processing method which eliminates the necessity for the heat curing. The influences of type of curing medium, duration and temperature of curing, and testing direction on the compressive strength of the printed geopolymer were investigated. The "green" printed geopolymer samples were immersed in four different curing mediums, including two sodium (Na)-based, and two potassium (K)-based activators with different alkali modulus (SiO 2 /M 2 O where M = Na or K), and cured at two different curing temperatures (ambient temperature (23 • C) vs. 60 • C) for 7 and 28 days. The compressive strength of the "post-processed" printed geopolymer specimens was measured in two different testing directions, namely the binder jetting direction and layer stacking direction. The results showed that the 28-day compressive strength of the ambient temperature cured printed geopolymer sample was comparable to the 7-day compressive strength of the corresponding heat cured sample. Therefore, the feasibility of enhancing the strength of printed geopolymer by curing in an alkaline solution at ambient temperature was established. This developed post-processing method based on the ambient temperature curing is more viable and less energy-intensive, yet provides comparable strength, as compared to the previously developed post-processing method based on the heat curing. The results also showed that the strength of the printed geopolymer samples cured in the K-based activators was lower than that of the specimens cured in the Na-based activators.

show abstract

On the Development of Fly Ash-Based Geopolymer Concrete

Cited by 177 publications

References 3 publications

High performance cementitious composite from alkali-activated ladle slag reinforced with polypropylene fibers

High performance cementitious composite from alkali-activated ladle slag reinforced with polypropylene fibers

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

Post-processing Methods to Improve Strength of Particle-Bed 3D Printed Geopolymer for Digital Construction Applications

Contact Info

Product

Resources

About