Corrigendum to ‘Thermal shock reactions of ordinary portland cement and geopolymer concrete: Microstructural and mechanical investigation’ [Construct. Build. Mater. 196 (2019) 492–498]

This study presents an investigation into the durability of geopolymer concrete prepared using high calcium fly ash along with alkaline activators when exposed to 2% solution of sulfuric acid and 5% magnesium sulphate for up to 45 days. The durability was also assessed by measuring water absorption and sorptivity. Ordinary Portland cement concrete was also prepared as control concrete. The grades chosen for the investigation were M20, M40, and M60. The alkaline solution used for present study is the combination of sodium silicate and sodium hydroxide solution with the ratio of 2.50. The molarity of sodium hydroxide was fixed as 12. The test specimens were150×150×150 mm cubes,100×200 mm cylinders, and100×50 mm discs cured at ambient temperature. Surface deterioration, density, and strength over a period of 14, 28, and 45 days were observed. The results of geopolymer and ordinary Portland cement concrete were compared and discussed. After 45 days of exposure to the magnesium sulfate solution, the reduction in strength was up to 12% for geopolymer concrete and up to 25% for ordinary Portland cement concrete. After the same period of exposure to the sulphuric acid solution, the compressive strength decrease was up to 20% for geopolymer concrete and up to 28% for ordinary Portland cement concrete.

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Effect of Ordinary Portland Cement on Some Properties of Pervious Geopolymer Concrete

Engineering and Technology Journal ◽

10.30684/etj.v39i4a.1793 ◽

2021 ◽

Vol 39 (4A) ◽

pp. 668-674

Author(s):

Wasan I. Khalіl ◽

Qaіs J. Frayyeh ◽

Haider Abed

Keyword(s):

Thermal Conductivity ◽

Compressive Strength ◽

Flexural Strength ◽

Portland Cement ◽

Ordinary Portland Cement ◽

Total Content ◽

Dry Density ◽

Geopolymer Concrete ◽

Naoh Solution

In this research, a study is made on the Pervious Geopolymer Concrete (PGC), which is based on localmaterial(Metakaolin). The inclusion of Ordinary Portland Cement (OPC) as a partial substitute for Metakaolin (MK) for the production of (PGCs) has also been investigated. Pervious Geopolymer concrete was outputted from the local Metakaolin (MK), and ordinary Portland cement (OPC) as a partial substitute by weight of MK and silicate of sodium (Na2SiO3) and hydroxide of sodium (NaOH) solution. All PGC samples were cured after 24 hours from casting for five hours at a degree of the temperature of 50 ° C, then the testingafter 28 days. The compressive-strength, total content of voids, the strength of bending, dry-density, and thermal-conductivity of pervious Geopolymer concrete were examined. The mechanicalresults of testing ranged from (11.03 and 2.25) to (14.3 and 2.75) MPa for compressive-strength and flexural strength respectively.

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Effect of Elevated Temperature on Alkali Activated Slag and Fly Ash based Geopolymer Concrete

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.d7935.049420 ◽

2020 ◽

Vol 9 (4) ◽

pp. 1241-1250

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Fly Ash ◽

Flexural Strength ◽

Portland Cement ◽

Ordinary Portland Cement ◽

Geopolymer Concrete ◽

Base Materials ◽

Activated Slag ◽

Alkali Activated

Activated Slag (AAS) and Fly Ash (FA) based geopolymer concrete a new blended alkali-activated concrete that has been progressively studied over the past years because of its environmental benefits superior engineering properties. Geopolymer has many favorable characteristics in comparison to Ordinary Portland Cement. Many base materials could be utilized to make geopolymer with the convenient concentration of activator solution. In this study, the experimental program composed of two phases; phase on divided into four groups; Group one deliberated the effect of sodium hydroxide molarity and different curing condition on compressive strength. Group two studied the effect of alkali activated solution (NaOH and Na2SiO3) content on compressive strength and workability. The effect of sand replacement with slag on compressive strength and workability was explained in group three. Group four studied the effect of slag replacement with several base materials Fly Ash (FA), Ordinary Portland Cement (OPC), pulverized Red Brick (PRB), and Meta Kaolin (MK). Phase two contains three mixtures from phase one which had the highest compressive strength. For each mixture, the fresh concrete test was air content. In addition the hardened concrete tests were the compressive strength at 3, 7, 28, 90, 180, and 365 days, the flexural strength at 28, 90, and 365 days, and the young's modulus at 28, 90, and 365 days. Moreover; the three mixtures were exposed to elevated temperature at 100oC, 300oC, and 600oC to study the effect of elevated temperature on compressive and flexural strength.

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An Experimental Evaluation of Development Length of Reinforcements Embedded in Geopolymer Concrete

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.578-579.441 ◽

2014 ◽

Vol 578-579 ◽

pp. 441-444 ◽

Cited By ~ 7

Author(s):

Jee Sang Kim ◽

Jongho Park

Keyword(s):

Portland Cement ◽

Ordinary Portland Cement ◽

Construction Material ◽

Geopolymer Concrete ◽

Development Length ◽

Reinforcing Bars ◽

Bond Slip ◽

Ordinary Concrete ◽

Pull Out

Geopolymer concrete is an emerging construction material that uses a by-product material such as fly ash to completely replace the ordinary Portland cement. This material is being studied extensively and shows promise as a greener substitute for ordinary Portland cement. This paper evaluates the bond strength and development length of reinforcements embedded in geopolymer concrete with reinforcing steel using pull-out tests. The test according to EN 10080 was carried out on 27 specimens for three kinds of geopolymer concrete of 20, 30 and 40 MPa compressive strength and 10, 16 and 35 mm diameter reinforcing bars. The tests show that the bond strengths in geopolymer concrete were decreased as the diameter of reinforcement increased as in ordinary concrete and the values were greater than those in ordinary concrete. Also, the bond-slip curves were obtained which have similar shape with those of ordinary concrete. The equation for the determination of development length based on this experiment was proposed.

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Effect of Alkali Activator Ratio on Mechanical Properties of GGBS based Geopolymer Concrete

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

10.35940/ijitee.j9539.1081219 ◽

2019 ◽

Vol 8 (12) ◽

pp. 947-952 ◽

Cited By ~ 1

Keyword(s):

Portland Cement ◽

Sodium Hydroxide ◽

Construction Projects ◽

Ordinary Portland Cement ◽

Geopolymer Concrete ◽

Flexural Test ◽

Co2 Gas ◽

Alkali Activator ◽

Carbon Dioxide Co2 ◽

Ambient Curing

Geopolymer concrete also referred to as “green” and “environmentally friendly” concrete is carbon free binding material which can be ultimate replacement for traditional Ordinary Portland cement (OPC) concrete. OPC production is solely responsible for seven percentage (7%) of carbon dioxide (CO2 ) gas emission globally. Taken in account, the serious threats imposed by ordinary Portland cement in coming future with its increasing use in construction projects, ecofriendly geopolymer concrete which aren’t harassing to surroundings will be a boon in Civil engineering field. Here, in this paper we studied the behavior of Geopolymer Concrete using (GGBS) under the effect of varying concentration of Alkali Activators. The alkali activators Sodium Hydroxide (NaOH) and Sodium Silicate (Na2SiO3 ) with Alkali Activator ratio (AAR) of 1:1.5, 1:2 & 1:2.5 were used. Also, the molarity of NaOH was altered for 8Molar, 10Molar and 12Molar. The specimens were casted for Compressive, Split Tensile and Flexural test and were tested after 7 days and 28 days of ambient curing. It was observed that Compressive, Split Tensile and Flexural strength of the GPC specimen increased with increasing molarity of Sodium Hydroxide (NaOH) and with increase in Alkali Activator Ratio

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Experimental investigations on compressive, impact and prediction of stress-strain of fly ash-geopolymer and portland cement concrete

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0036 ◽

2020 ◽

Vol 40 (7) ◽

pp. 583-590

Author(s):

Nagajothi S ◽

Elavenil S

Keyword(s):

Portland Cement ◽

Ordinary Portland Cement ◽

Impact Resistance ◽

Geopolymer Concrete ◽

Portland Cement Concrete ◽

Cement Concrete ◽

Stress Strain ◽

River Sand ◽

Conventional Concrete ◽

Strain Behaviour

AbstractThe recent technology of geopolymer concrete is a substitute material for ordinary portland cement concrete which is produced from the polycondensation reaction of aluminosilicate materials with alkaline activator solutions. The cost of river sand is high since the demand for the same is also high. Manufactured sand is used as a replacement material for river sand in geopolymer concrete. This paper mainly focuses to find the properties of fly ash (FA) – based geopolymer concrete under ambient cured temperature like compressive strength, stress strain behaviour, modulus of elasticity, Poission’s ratio and impact resistance. The result of geopolymer concrete is compared with ordinary portland cement concrete. The elasticity modulus and Poission’s ratio of geopolymer concrete are lower than conventional concrete. The Stress-strain behaviour of geopolymer concrete is similar to conventional concrete. The impact resistance of geopolymer concrete is very good when compared with conventional concrete.

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Effect of Geopolymer Concrete Infill on Profiled Steel Sheeting Half Dry Board (PSSHDB) Floor System Subjected to Bending Moment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.754-755.354 ◽

2015 ◽

Vol 754-755 ◽

pp. 354-358

Author(s):

Mohd Isa Jaffar ◽

Wan Hamidon Wan Badaruzzaman ◽

Mohd Mustafa Al Bakri Abdullah ◽

Kartini Kamarulzaman ◽

Mahmood Seraji

Keyword(s):

Compressive Strength ◽

Portland Cement ◽

Laboratory Experiments ◽

Ordinary Portland Cement ◽

Bending Moment ◽

Research Approach ◽

Geopolymer Concrete ◽

Structural System ◽

Normal Concrete ◽

Floor System

Profiled Steel sheeting Dry Board (PSSDB) system is a lightweight composite structural system consisting of profiled steel sheeting, mechanically connected to a dry board using self-drilling and self-tapping screw. The objective of this study is to investigate the effect of geopolymer concrete infill in PSSDB system with half board (PSSHDB), focus on its deflection serviceability limit at mid-span region. Geopolymer concrete was chosen to be as infill in the PSSDB floor system due to its high compressive strength as compared to normal concrete and its potential as an alternative concrete since it does not utilize Ordinary Portland Cement (OPC). This study used a modified PSSHDB panel using a half-sized dry board. In achieving this objective, forecasting the behavior of the system in laboratory experiments will be taken into account as the research approach. Experimental results found that with the use of geopolymer concrete infill, the mid-span deflection on the PSSHDB floor system can be reduced to 41% as compared to the use of normal concrete infill. This indicates an increase in the stiffness of this system due to the effect of infill geopolymer concrete.

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