Optimum Mix for Pervious Geopolymer Concrete (GEOCRETE) Based on Water Permeability and Compressive Strength

The use of fluid catalytic cracking (FCC) by-products as aluminosilicate precursors in geopolymer binders has attracted significant interest from researchers in recent years owing to their high alumina and silica contents. Introduced in this study is the use of geopolymer concrete comprising FCC residue combined with fly ash as the requisite source of aluminosilicate. Fly ash was replaced with various FCC residue contents ranging from 0–100% by mass of binder. Results from standard testing methods showed that geopolymer concrete rheological properties such as yield stress and plastic viscosity as well as mechanical properties including compressive strength, flexural strength, and elastic modulus were affected significantly by the FCC residue content. With alkali liquid to geopolymer solid ratios (AL:GS) of 0.4 and 0.5, a reduction in compressive and flexural strength was observed in the case of geopolymer concrete with increasing FCC residue content. On the contrary, geopolymer concrete with increasing FCC residue content exhibited improved strength with an AL:GS ratio of 0.65. Relationships enabling estimation of geopolymer elastic modulus based on compressive strength were investigated. Scanning electron microscope (SEM) images and X-ray diffraction (XRD) patterns revealed that the final product from the geopolymerization process consisting of FCC residue was similar to fly ash-based geopolymer concrete. These observations highlight the potential of FCC residue as an aluminosilicate source for geopolymer products.

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Microstructure and Mechanical Properties of Ambiently-Cured Blended Coal Ash-Based Geopolymer Concrete

Materials Science Forum ◽

10.4028/www.scientific.net/msf.857.400 ◽

2016 ◽

Vol 857 ◽

pp. 400-404

Author(s):

Tian Yu Xie ◽

Togay Ozbakkaloglu

Keyword(s):

Mechanical Properties ◽

Experimental Study ◽

Compressive Strength ◽

Fly Ash ◽

Bottom Ash ◽

Coal Ash ◽

Geopolymer Concrete ◽

Mass Ratio ◽

Blended Coal ◽

Microstructure And Mechanical Properties

This paper presents the results of an experimental study on the behavior of fly ash-, bottom ash-, and blended fly and bottom ash-based geopolymer concrete (GPC) cured at ambient temperature. Four bathes of GPC were manufactured to investigate the influence of the fly ash-to-bottom ash mass ratio on the microstructure, compressive strength and elastic modulus of GPC. All the results indicate that the mass ratio of fly ash-to-bottom ash significantly affects the microstructure and mechanical properties of GPCs

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Novel Analytical Method for Mix Design and Performance Prediction of High Calcium Fly Ash Geopolymer Concrete

Polymers ◽

10.3390/polym13060900 ◽

2021 ◽

Vol 13 (6) ◽

pp. 900

Author(s):

Chamila Gunasekara ◽

Peter Atzarakis ◽

Weena Lokuge ◽

David W. Law ◽

Sujeeva Setunge

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Gradient Algorithm ◽

Geopolymer Concrete ◽

Statistical Regression ◽

Solid Ratio ◽

Marquardt Algorithm ◽

High Calcium ◽

High Calcium Fly Ash ◽

Matlab Programming

Despite extensive in-depth research into high calcium fly ash geopolymer concretes and a number of proposed methods to calculate the mix proportions, no universally applicable method to determine the mix proportions has been developed. This paper uses an artificial neural network (ANN) machine learning toolbox in a MATLAB programming environment together with a Bayesian regularization algorithm, the Levenberg-Marquardt algorithm and a scaled conjugate gradient algorithm to attain a specified target compressive strength at 28 days. The relationship between the four key parameters, namely water/solid ratio, alkaline activator/binder ratio, Na2SiO3/NaOH ratio and NaOH molarity, and the compressive strength of geopolymer concrete is determined. The geopolymer concrete mix proportions based on the ANN algorithm model and contour plots developed were experimentally validated. Thus, the proposed method can be used to determine mix designs for high calcium fly ash geopolymer concrete in the range 25–45 MPa at 28 days. In addition, the design equations developed using the statistical regression model provide an insight to predict tensile strength and elastic modulus for a given compressive strength.

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Improving the structural performance of reinforced geopolymer concrete incorporated with hazardous heavy metal waste ash

World Journal of Engineering ◽

10.1108/wje-01-2021-0055 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Suresh Kumar Arunachalam ◽

Muthukannan Muthiah ◽

Kanniga Devi Rangaswamy ◽

Arunkumar Kadarkarai ◽

Chithambar Ganesh Arunasankar

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Medical Waste ◽

Source Material ◽

Geopolymer Concrete ◽

Deformation Capacity ◽

Cement Concrete ◽

Content Type ◽

Load Carrying ◽

Reinforced Cement

Purpose Demand for Geopolymer concrete (GPC) has increased recently because of its many benefits, including being environmentally sustainable, extremely tolerant to high temperature and chemical attacks in more dangerous environments. Like standard concrete, GPC also has low tensile strength and deformation capacity. This paper aims to analyse the utilization of incinerated bio-medical waste ash (IBWA) combined with ground granulated blast furnace slag (GGBS) in reinforced GPC beams and columns. Medical waste was produced in the health-care industry, specifically in hospitals and diagnostic laboratories. GGBS is a form of industrial waste generated by steel factories. The best option to address global warming is to reduce the consumption of Portland cement production and promote other types of cement that were not a pollutant to the environment. Therefore, the replacement in ordinary Portland cement construction with GPC is a promising way of reducing carbon dioxide emissions. GPC was produced due to an alkali-activated polymeric reaction between alumina-silicate source materials and unreacted aggregates and other materials. Industrial pollutants such as fly ash and slag were used as raw materials. Design/methodology/approach Laboratory experiments were performed on three different proportions (reinforced cement concrete [RCC], 100% GGBS as an aluminosilicate source material in reinforced geopolymer concrete [GRGPC] and 30% replacement of IBWA as an aluminosilicate source material for GGBS in reinforced geopolymer concrete [IGRGPC]). The cubes and cylinders for these proportions were tested to find their compressive strength and split tensile strength. In addition, beams (deflection factor, ductility factor, flexural strength, degradation of stiffness and toughness index) and columns (load-carrying ability, stress-strain behaviour and load-deflection behaviours) of reinforced geopolymer concrete (RGPC) were studied. Findings As shown by the results, compared to Reinforced Cement Concrete (RCC) and 100% GGBS based Reinforced Geopolymer Concrete (GRGPC), 30% IBWA and 70% GGBS based Reinforced Geopolymer Concrete (IGRGPC) (30% IBWA–70% GGBS reinforced geo-polymer concrete) cubes, cylinders, beams and columns exhibit high compressive strength, tensile strength, flexural strength, load-carrying ability, ultimate strength, stiffness, ductility and deformation capacity. Originality/value All the results were based on the experiments done in this research. All the result values obtained in this research are higher than the theoretical values.

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Strength and Durability Performance of Alkali-Activated Rice Husk Ash Geopolymer Mortar

The Scientific World JOURNAL ◽

10.1155/2014/209584 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 20

Author(s):

Yun Yong Kim ◽

Byung-Jae Lee ◽

Velu Saraswathy ◽

Seung-Jun Kwon

Keyword(s):

Compressive Strength ◽

Rice Husk ◽

Rice Husk Ash ◽

Polymerization Reaction ◽

Strength Development ◽

Geopolymer Concrete ◽

Portland Cement Concrete ◽

Mix Proportion ◽

Strength And Durability ◽

Alkali Activated

This paper describes the experimental investigation carried out to develop the geopolymer concrete based on alkali-activated rice husk ash (RHA) by sodium hydroxide with sodium silicate. Effect on method of curing and concentration of NaOH on compressive strength as well as the optimum mix proportion of geopolymer mortar was investigated. It is possible to achieve compressive strengths of 31 N/mm2and 45 N/mm2, respectively for the 10 M alkali-activated geopolymer mortar after 7 and 28 days of casting when cured for 24 hours at 60°C. Results indicated that the increase in curing period and concentration of alkali activator increased the compressive strength. Durability studies were carried out in acid and sulfate media such as H2SO4, HCl, Na2SO4, and MgSO4environments and found that geopolymer concrete showed very less weight loss when compared to steam-cured mortar specimens. In addition, fluorescent optical microscopy and X-ray diffraction (XRD) studies have shown the formation of new peaks and enhanced the polymerization reaction which is responsible for strength development and hence RHA has great potential as a substitute for ordinary Portland cement concrete.

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Resistance to Sulfuric Acid Corrosion of Geopolymer Concrete Based on Different Binding Materials and Alkali Concentrations

Materials ◽

10.3390/ma14237109 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7109

Author(s):

Wei Yang ◽

Pinghua Zhu ◽

Hui Liu ◽

Xinjie Wang ◽

Wei Ge ◽

...

Keyword(s):

Compressive Strength ◽

Corrosion Resistance ◽

Sulfuric Acid ◽

Fly Ash ◽

Acid Corrosion ◽

Geopolymer Concrete ◽

High Calcium ◽

High Calcium Fly Ash ◽

Naoh Solution ◽

Sulfuric Acid Corrosion

Geopolymer binder is expected to be an optimum alternative to Portland cement due to its excellent engineering properties of high strength, acid corrosion resistance, low permeability, good chemical resistance, and excellent fire resistance. To study the sulfuric acid corrosion resistance of geopolymer concrete (GPC) with different binding materials and concentrations of sodium hydroxide solution (NaOH), metakaolin, high-calcium fly ash, and low-calcium fly ash were chosen as binding materials of GPC for the geopolymerization process. A mixture of sodium silicate solution (Na2SiO3) and NaOH solution with different concentrations (8 M and 12 M) was selected as the alkaline activator with a ratio (Na2SiO3/NaOH) of 1.5. GPC specimens were immersed in the sulfuric acid solution with the pH value of 1 for 6 days and then naturally dried for 1 day until 98 days. The macroscopic properties of GPC were characterized by visual appearance, compressive strength, mass loss, and neutralization depth. The materials were characterized by SEM, XRD, and FTIR. The results indicated that at the immersion time of 28 d, the compressive strength of two types of fly ash-based GPC increased to some extent due to the presence of gypsum, but this phenomenon was not observed in metakaolin-based GPC. After 98 d of immersion, the residual strength of fly ash based GPC was still higher, which reached more than 25 MPa, while the metakaolin-based GPC failed. Furthermore, due to the rigid 3D networks of aluminosilicate in fly ash-based GPC, the mass of all GPC decreased slightly during the immersion period, and then tended to be stable in the later period. On the contrary, in metakaolin-based GPC, the incomplete geopolymerization led to the compressive strength being too low to meet the application of practical engineering. In addition, the compressive strength of GPC activated by 12 M NaOH was higher than the GPC activated by 8 M NaOH, which is owing to the formation of gel depended on the concentration of alkali OH ion, low NaOH concentration weakened chemical reaction, and reduced compressive strength. Additionally, according to the testing results of neutralization depth, the neutralization depth of high-calcium fly ash-based GPC activated by 12 M NaOH suffered acid attack for 98 d was only 6.9 mm, which is the minimum value. Therefore, the best performance was observed in GPC prepared with high-calcium fly ash and 12 M NaOH solution, which is attributed to gypsum crystals that block the pores of the specimen and improve the microstructure of GPC, inhibiting further corrosion of sulfuric acid.

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Study of Proportional Variation of Geopolymer Concrete which Self Compacting Concrete

Journal of Advanced Civil and Environmental Engineering ◽

10.30659/jacee.2.2.65-75 ◽

2019 ◽

Vol 2 (2) ◽

pp. 65

Author(s):

Purwanto P. ◽

Himawan Indarto

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Power Plant ◽

Portland Cement ◽

Fine Aggregate ◽

Geopolymer Concrete ◽

Conventional Concrete ◽

Basic Characteristics ◽

Carbon Dioxide Co2 ◽

Proportional Variation

Portland cement production process which is the conventional concrete constituent materials always has an impact on producing carbon dioxide (CO2) which will damage the environment. To maintain the continuity of development, while maintaining the environment, Portland cement substitution can be made with more environmentally friendly materials, namely fly ash. The substitution of fly ash material in concrete is known as geopolymer concrete. Fly ash is one of the industrial waste materials that can be used as geopolymer material. Fly ash is mineral residue in fine grains produced from coal combustion which is mashed at power plant power plant [15]. Many cement factories have used fly ash as mixture in cement, namely Portland Pozzolan Cement. Because fly ash contains SiO2, Al2O3, P2O3, and Fe2O3 which are quite high, so fly ash is considered capable of replacing cement completely.This study aims to obtain geopolymer concrete which has the best workability so that it is easy to work on (Workable Geopolymer Concrete / Self Compacting Geopolymer Concrete) and obtain the basic characteristics of geopolymer concrete material in the form of good workability and compressive strength. In this study, geopolymer concrete is composed of coarse aggregate, fine aggregate, fly ash type F, and activators in the form of NaOH and Na2SiO3 Be52. In making geopolymer concrete, additional ingredients such as superplastizer are added to increase the workability of geopolymer concrete. From this research, the results of concrete compressive strength above fc' 25 MPa and horizontal slump values reached 60 to 80 centimeters.

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Effect of Na2SiO3/Naoh on the Compressive Strength of Inorganic Polymer Concrete Mixed with Ground Granulated Blast Furnace Slag (GGBS) At Ambient Condition

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.a4844.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 1222-1228

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Ambient Condition ◽

Polymer Concrete ◽

Geopolymer Concrete ◽

Split Tensile Strength ◽

Standard Size ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

This paper aims to investigate the influence of alkaline activators solution i.e, Na2SiO3 / NaOH on compressive strength of geopolymer concrete mixed with Ground Granulated Blast furnace slag (GGBS) for constant molarity 8 M. The ratio of alkali to binder ratio is taken as 0.5 and the ratio of Na2SiO3 / NaOH is 2.5. The geopolymer mix is based on pervious sutdies. As per Indian standard size moulds for the cube, cylinder and prism are cast, cured and tested.The specimens were tested for fresh concrete properties such as slump cone test and hardened properties such as compressive strength for cubes, split tensile strength for cylinders and flexural strength for prism different days of curing under ambient temperature. Also, a microstructural study is done by using Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) for the tested sample. It is found from the test results that, with the aid of alumino-silicate solution, early strength is achieved by geopolymer concrete within 7 days under ambient condition due to the presence of ground granulated slag.

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Research on Mechanical Performance & Behaviour of Geopolymer Concrete Subjected to Elevated Temperatures

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1001.0882s819 ◽

2019 ◽

Vol 8 (2S8) ◽

pp. 883-887

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Silica Fume ◽

Elevated Temperatures ◽

Mechanical Performance ◽

Geopolymer Concrete ◽

Sem Images ◽

Before And After ◽

Alkaline Conditions ◽

Compressive Strength Of Concrete

The investigative studies on mechanical performance & behaviour, of Geopolymer Concrete (GPC) before and after the exposure to elevated temperatures (of 200 0 C -1000 0 C with an increment of 100 0 C). Indicate that the GPC Specimens Exhibited better Compressive strength at higher temperatures than that of those made by regular OPC Concrete with M30 Grade. The chronological changes in the geopolymeric structure upon exposure to these temperatures and their reflections on the thermal behaviour have also been explored. The SEM images indicate GPC produced by fly ash , metakaolin and silica fume, under alkaline conditions form Mineral binders that are not only non-flammable and but are also non-combustible resins and binders. Further the Observations drawn disclose that the mass and compressive strength of concrete gets reduced with increase in temperatures.

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