Effects of waste glass sand on the thermal behavior and strength of fly ash and GGBS based alkali activated mortar exposed to elevated temperature

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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The influence of CO2 accelerated carbonation on alkali-activated fly ash cement under elevated temperature and pressure

Materialwissenschaft und Werkstofftechnik ◽

10.1002/mawe.201800029 ◽

2018 ◽

Vol 49 (4) ◽

pp. 483-488 ◽

Cited By ~ 1

Author(s):

S. Ridha ◽

R.A. Setiawan ◽

A.I. Abd Hamid ◽

A.R. Shahari

Keyword(s):

Elevated Temperature ◽

Fly Ash ◽

Accelerated Carbonation ◽

Temperature And Pressure ◽

Alkali Activated

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Numerical and experimental studies on sustainable alkali activated concretes at elevated temperatures

Journal of Structural Fire Engineering ◽

10.1108/jsfe-02-2019-0014 ◽

2019 ◽

Vol ahead-of-print (ahead-of-print) ◽

Cited By ~ 1

Author(s):

Subhash Yaragal ◽

Chethan Kumar B. ◽

Manoj Uddavolu Abhinav

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Fly Ash ◽

Elevated Temperatures ◽

Experimental Studies ◽

Optimization Techniques ◽

Gray Relational Analysis ◽

Complete Replacement ◽

Content Type ◽

Alkali Activated

Purpose To reduce environmental impact caused by excessive use of ordinary Portland cement (OPC) and to mitigate scarcity of base materials such as natural coarse aggregate (NCA), industrial by-products can be carefully used as alternatives to OPC and NCA, in production of concrete. This paper aims to describe the performance of using ground granulated blast furnace slag (GGBS), fly ash (FA) as a complete replacement to OPC and ferrochrome slag (FCS) as replacement to NCA in production of novel FCS based alkali activated slag/fly ash concretes (AASFC) and evaluate their performance at elevated temperatures. Design/methodology/approach Two control factors with three levels each i.e. FA (0, 25 and 50 per cent by weight) and FCS (0, 50 and 100 per cent by volume) as a GGBS and NCA replacement, respectively, were adopted in AASFC mixtures. Further, AASFC mixture specimens were subjected to different levels of elevated temperature, i.e. 200°C, 400°C, 600°C and 800°C. Compressive strength and residual compressive strength were considered as responses. Three different optimization techniques i.e. gray relational analysis, technique for order preference by similarity to ideal solution and Desirability function approach were used to optimize AASFC mixtures subjected to elevated temperatures. Findings As FA replacement increases in FCS based AASFC mixtures, workability increases and compressive strength decreases. The introduction of FCS as replacement to NCA in AASFC mixture did not show any significant change in compressive strength under ambient condition. AASFC produced with 75 per cent GGBS, 25 per cent FA and 100 per cent FCS was found to have excellent elevated temperature enduring properties among all other AASFC mixtures studied. Originality/value Although several studies are available on using GGBS, FA and FCS in production of OPC-based concretes, present study reports the performance of novel FCS based AASFC mixtures subjected to elevated temperatures. Further, GGBS, FA and FCS used in the present investigation significantly reduces CO2 emission and environmental degradation associated with OPC production and NCA extraction, respectively.

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Waste glass as binder in alkali activated slag–fly ash mortars

Materials and Structures ◽

10.1617/s11527-019-1404-3 ◽

2019 ◽

Vol 52 (5) ◽

Cited By ~ 2

Author(s):

G. Liu ◽

M. V. A. Florea ◽

H. J. H. Brouwers

Keyword(s):

Fly Ash ◽

Glass Powder ◽

Reference Sample ◽

Drying Shrinkage ◽

Waste Glass ◽

Reaction Products ◽

Alkali Activated Slag ◽

Carbonation Resistance ◽

Activated Slag ◽

Alkali Activated

Abstract This paper illustrates the application of waste glass powder as part of the binder in slag–fly ash systems activated by NaOH and NaOH/Na2CO3 activators. To evaluate the reaction kinetics, reaction products, mechanical properties, and durability performance of glass powder modified alkali activated slag–fly ash systems, calorimetry test, X-ray diffraction, FTIR, strength test, drying shrinkage tests, and carbonation test were conducted. From the isothermal calorimeter results, glass powder shows a higher reactivity compared to fly ash but still lower than slag. The reaction products of glass power modified samples exhibit an enhancement of polymerization degree of Si–O–T, observed in FTIR. As a consequence, higher drying shrinkage exists in glass modified mortars. The mechanical performance of different samples is mostly controlled by the Ca/Si of dry mixtures and activator type. After the slag–fly ash binder system was modified by the waste glass, a significant enhancement of resistance to carbonation was identified, especially for NaOH/Na2CO3 activated mortars, which show an increase of 300% on the carbonation resistance ability compared to the reference sample. The Na/(Si + Al) ratio of dry mixtures exhibits a positive correlation with carbonation resistance.

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Use of Off-ASTM Class F Fly Ash and Waste Limestone Powder in Mortar Mixtures Containing Waste Glass Sand

Sustainability ◽

10.3390/su14010075 ◽

2021 ◽

Vol 14 (1) ◽

pp. 75

Author(s):

Chang-Seon Shon ◽

Aidyn Tugelbayev ◽

Ramazan Shaimakhanov ◽

Nariman Karatay ◽

Dichuan Zhang ◽

...

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Waste Glass ◽

Recycled Concrete ◽

Limestone Powder ◽

River Sand ◽

Single Use ◽

Glass Sand ◽

Class F Fly Ash ◽

Class F

Developing sustainable concrete with less ordinary Portland cement is a growing issue in the construction industry. Incorporating industrial by-products (such as fly ash or slag) or municipal solid wastes (such as waste glass or recycled concrete aggregate) into the concrete becomes an effective way to reduce the consumption of natural sources and carbon dioxide emission if a proper mix design is provided. The present study examines the influence of the combined use of off-ASTM Class F fly ash (FFA) and waste limestone powder (LSP) on flowability, compressive strength, and expansion characteristics of mortar mixtures containing waste glass sand (WGS). FFA and LSP were used as cement replacement while WGS was used as partial reactive siliceous river sand replacement. Material variables included different WGS replacement ratios (25%, 50%, and 75%) with river sand, LSP contents (25%, 50%, and 75%), FFA contents (15%, 30%, and 45%), and different combinations of FFA-LSP (15–10%, 15–15%, 15–30%, and 15–35%). It is shown that the single use of FFA or LSP reduces both compressive strength and flowability of mortar mixture as its replacement level increases. However, mixtures combined with FFA and LSP provide higher or comparable strength to the single LSP or FFA mixture. For the expansion characteristics due to alkali-silica reaction, the single-use of more than 30% FFA or 75% LSP has less than 0.1% expansion, which is a non-reactive aggregate criterion based on the C1260/C1567 when the test period is extended to 56 days. Moreover, the combination of FFA and LSP has a considerable reduction in expansion rate compared to the single FFA or LSP mixture.

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