A STUDY ON THE VARIATION OF STRENGTH PROPERTIES OF CONCRETE WITH PARTIAL REPLACEMENT OF CEMENT USING NANO-SILICA (NS) AND FLY ASH (FS)

In the current scenario nanotechnology and nanomaterials are emerging as key role in engineering and medical industries. The objective of this research is to increase the usage of fly ash in concrete to enhance the strength properties of concrete mixed with nano silica and to reduce the emission control caused by CO2discharged from cement manufacturing industries. The strength properties of concrete mixture is enhanced with nano size particles filled the voids amoung micron size cement particle, and hence a denser concrete mixture was being attained. Fly ash is used for partial replacement of cement to enhance the environmental sustainability and to reduce the cost. This research work focussed on preparation of nano silica mixed concrete with replacement of fly ash in concrete mixture. Nano silica was added in addition to the above by 1% and 2% to improve the overall strength properties. Different experimental analysis were carried out to obtained the results such as compression strength, ultimate divide tensile strength and elastic modulus of the enriched concrete mixture. From the observed results it was found that, compression strength was increased by adding 1% nano silica and 25% of fly ash and also increased the ultimate tensile strength by 28%. Scanning Electrom Microscope (SEM) results reveal that, the incorporation of the nano silica in concrete increases the mechanical properties and porosity was successfully minimized with enhancement of pore size distribution.

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Optimisation of GBFS, Fly Ash, and Nano-Silica Contents in Alkali-Activated Mortars

Polymers ◽

10.3390/polym13162750 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2750

Author(s):

Hassan Amer Algaifi ◽

Abdeliazim Mustafa Mohamed ◽

Eyad Alsuhaibani ◽

Shahiron Shahidan ◽

Fahed Alrshoudi ◽

...

Keyword(s):

Fly Ash ◽

Strength Properties ◽

Partial Replacement ◽

Nano Silica ◽

Linear Quadratic ◽

Statistical Validation ◽

Glass Waste ◽

The Difference ◽

Strength And Durability ◽

Alkali Activated

Although free-cement-based alkali-activated paste, mortar, and concrete have been recognised as sustainable and environmental-friendly materials, a considerable amount of effort is still being channeled to ascertain the best binary or ternary binders that would satisfy the requirements of strength and durability as well as environmental aspects. In this study, the mechanical properties of alkali-activated mortar (AAM) made with binary binders, involving fly ash (FA) and granulated blast-furnace slag (GBFS) as well as bottle glass waste nano-silica powder (BGWNP), were opti-mised using both experimentally and optimisation modelling through three scenarios. In the first scenario, the addition of BGWNP varied from 5% to 20%, while FA and GBFS were kept constant (30:70). In the second and third scenarios, BGWNP (5–20%) was added as the partial replacement of FA and GBFS, separately. The results show that the combination of binary binders (FA and GBFS) and BGWNP increased AAM’s strength compared to that of the control mixture for all scenarios. In addition, the findings also demonstrated that the replacement of FA by BGWNP was the most significant, while the effect of GBFS replacement by BGWNP was less significant. In particular, the highest improvement in compressive strength was recorded when FA, GBFS, and BGWNP were 61.6%, 30%, and 8.4%, respectively. Furthermore, the results of ANOVA (p values < 0.0001 and high F-values) as well as several statistical validation methods (R > 0.9, RAE < 0.1, RSE < 0.013, and RRSE < 0.116) confirmed that all the models were robust, reliable, and significant. Similarly, the data variation was found to be less than 5%, and the difference between the predicted R2 and adj. R2 was very small (<0.2), thus confirming that the proposed non-linear quadratic equations had the capability to predict for further observation. In conclusion, the use of BGWNP in AAM could act as a beneficial and sustainable strategy, not only to address environmental issues (e.g., landfill) but to also enhance strength properties.

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Partial Replacement of Cement by Neem Leaves Ash and Fly Ash

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.a1545.059120 ◽

2020 ◽

Vol 9 (1) ◽

pp. 506-508

Keyword(s):

Experimental Investigation ◽

Fly Ash ◽

Ordinary Portland Cement ◽

Construction Materials ◽

Strength Properties ◽

Vital Role ◽

Partial Replacement ◽

Cement Ratio ◽

Neem Leaves ◽

The World

Concrete is the most essential construction materials in all over the world. It is necessary to search the cheaply obtainable material as admixture which might be partially replaced cement in the production of concrete. This project is an experimental investigation of the neem leaves ash as partial replacement for cement also fly ash is used for partial replacement of cement. The neem leaves were dried, burnt and heated in the furnace to produce Neem leaves Ash, which was discovered to posses Pozzolanic properties.the ordinary Portland cement was replaced by neem ash by 5%,10%,15%,20% and 25% by weight also flash replaced by 15%,20%,25% and 30% the cubes were crushed to know the comparative strength of the concrete at different curing days. The last result showed that workability and strength properties of the concrete was depended on water cement ratio, total days of curing, the percentage of replacement of Neem leaves ash for OPC . I. This project it was noticed that the result of 5% NLA and 15% fly ash and 10% NLA and 20% of fly ash were gradually increasing the strength at 28 days. Neem leaves play a vital role and behaviour of Neem leaves ash and flash used concrete will be studied

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Effect of Nano-Silica and GGBS on the Strength Properties of Fly Ash-Based Geopolymers

Lecture Notes in Civil Engineering - Sustainable Construction and Building Materials ◽

10.1007/978-981-13-3317-0_40 ◽

2018 ◽

pp. 449-458

Author(s):

A. Ravitheja ◽

N. L. N. Kiran Kumar

Keyword(s):

Fly Ash ◽

Strength Properties ◽

Nano Silica

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High Volume Slag and Slag-Fly Ash Blended Cement Pastes Containing Nano Silica

Materials Science Forum ◽

10.4028/www.scientific.net/msf.967.205 ◽

2019 ◽

Vol 967 ◽

pp. 205-213

Author(s):

Faiz U.A. Shaikh ◽

Anwar Hosan

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Cement Paste ◽

Ordinary Portland Cement ◽

Blended Cement ◽

High Volume ◽

Ash Content ◽

Partial Replacement ◽

Nano Silica ◽

Cement Pastes

This paper presents the effect of nanosilica (NS) on compressive strength and microstructure of cement paste containing high volume slag and high volume slag-fly ash blend as partial replacement of ordinary Portland cement (OPC). Results show that high volume slag (HVS) cement paste containing 60% slag exhibited about 4% higher compressive strength than control cement paste, while the HVS cement paste containing 70% slag maintained the similar compressive strength to control cement paste. However, about 9% and 37% reduction in compressive strength in HVS cement pastes is observed due to use of 80% and 90% slag, respectively. The high volume slag-fly ash (HVSFA) cement pastes containing total slag and fly ash content of 60% exhibited about 5%-16% higher compressive strength than control cement paste. However, significant reduction in compressive strength is observed in higher slag-fly ash blends with increasing in fly ash contents. Results also show that the addition of 1-4% NS improves the compressive strength of HVS cement paste containing 70% slag by about 9-24%. However, at higher slag contents of 80% and 90% this improvement is even higher e.g. 11-29% and 17-41%, respectively. The NS addition also improves the compressive strength by about 1-59% and 5-21% in high volume slag-fly ash cement pastes containing 21% fly ash+49%slag and 24% fly ash+56%slag, respectively. The thermogravimetric analysis (TGA) results confirm the reduction of calcium hydroxide (CH) in HVS/HVSFA pastes containing NS indicating the formation of additional calcium silicate hydrate (CSH) gels in the system. By combining slag, fly ash and NS in high volumes e.g. 70-80%, the carbon footprint of cement paste is reduced by 66-76% while maintains the similar compressive strength of control cement paste. Keywords: high volume slag, nanosilica, compressive strength, TGA, high volume slag-fly ash blend, CO2 emission.

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Influence of Fly Ash and Basalt Fibers on Strength and Chloride Penetration Resistance of Self-Consolidating Concrete

Materials Science Forum ◽

10.4028/www.scientific.net/msf.866.3 ◽

2016 ◽

Vol 866 ◽

pp. 3-8 ◽

Cited By ~ 8

Author(s):

Osama Ahmed Mohamed ◽

Waddah Al Hawat

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Portland Cement ◽

Strength Properties ◽

Chloride Penetration ◽

Partial Replacement ◽

Basalt Fibers ◽

Self Consolidating Concrete ◽

Chloride Penetration Resistance ◽

Hardened Properties

Fly ash is a sustainable partial replacement of Portland cement that offers significant advantages in terms of fresh and hardened properties of concrete. This paper presents the findings of a study that aims at assessing the durability and strength properties of sustainable self-consolidating concrete (SCC) mixes in which Portland cement was partially replaced with 10%, 20%, 30%, and 40% fly ash. The study confirms that replacing Portland cement with fly ash at all of the percentages studied improves resistance of concrete to chloride penetration. The 40% fly ash mix exhibited the highest resistance to chloride penetration compared to the control mix. Despite the relative drop in compressive strength after 7 days of curing, the 28-day compressive strength of 40% SCC mix reached 55.75 MP, which is very close to the control mix. The study also confirms that adding 1%, 1.5%, and 2% basalt fibers, respectively, to the 40% fly ash mix improves the resistance to chloride penetration compared to the mix without basalt fibers.

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Study on Strength Properties of Pervious Concrete by Partial Replacement of Cement with Fly Ash

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.38161 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1211-1227

Author(s):

Wasiq Maqbool Peer

Keyword(s):

Fly Ash ◽

Green Building ◽

Strength Properties ◽

Raw Material ◽

Pervious Concrete ◽

Partial Replacement ◽

Fine Aggregate ◽

Conventional Concrete ◽

Natural Choice ◽

Structural Applications

Abstract: Pervious concrete is a concrete containing little or no fine aggregate; it consists of coarse aggregate and cement paste. It seems pervious concrete would be a natural choice for use in structural applications in this age of ‘green building’. It consumes less raw material than normal concrete (no sand), it provides superior insulation values when used in walls, and through the direct drainage of rainwater, it helps recharge groundwater in pavement applications. Due to increase in construction and demolition activities all over the world, the waste concrete after the destruction is not used for any purpose which leads to loss of economy of the country. India is a developing country where urbanization is increasing rapidly which in turn leading to increase of drainage facilities. Pervious concrete helps to allow the water flow into the ground due to interconnected pores. Natural aggregate is becoming scarce, production and shipment is becoming more difficult. In order to overcome this problem, there is need to find a by-product, which can be used to replace the aggregate in conventional concrete mix. Keywords: Pervious Concrete, Partial Replacement, Fly Ash, Cement, Compressive Strength,

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Effect of Ceramic Aggregate and Fly ash in Normal Strength Concrete

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a1015.1291s419 ◽

2019 ◽

Vol 9 (1S3) ◽

pp. 479-482

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Fly Ash ◽

Thermal Power ◽

Strength Properties ◽

Partial Replacement ◽

Sieve Analysis ◽

Normal Strength Concrete ◽

Ceramic Insulator ◽

Normal Strength

In this study, full and partial replacement of stone aggregate by ceramic insulator scrap and partial replacement of cement by fly ash has been done in order to enhance economy in construction. More once, the solution of disposal of wasting from ceramic insulator manufacturing company and thermal power plant is also achieved. Further various mechanical properties of ceramic insulator scrap such as crushing value, impact value, abrasion value, specific gravity, sieve analysis and water absorption has been studied and obtained to make the study fruitful. Concrete of grade M15 is used to study the compressive strength properties of stone and ceramic aggregates. Replacement of stone aggregates by ceramic aggregates has been done in stages starting from 0% to 100% each stage possessing the variation of 10% and in all the specimens 30% of cement is replaced by 35% of fly ash. Six number of cube samples are cast for each variation and the compressive strength of the same have been obtained at 7, 28 and 56 days of age. Totally 216 cubes are cast and tested for compression. It is found that the optimum percentage at which the stone aggregate can be replaced by ceramic aggregates is 50% and 30% of cement can be replaced by 35% fly ash.

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Effect of Nano Silica and Ultrafine Fly Ash on Compressive Strength of High Volume Fly Ash Mortar

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.368-370.1061 ◽

2013 ◽

Vol 368-370 ◽

pp. 1061-1065 ◽

Cited By ~ 12

Author(s):

Steve W.M. Supit ◽

Faiz U.A. Shaikh ◽

Prabir K. Sarker

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

High Volume ◽

Partial Replacement ◽

Strength Development ◽

Test Results ◽

X Ray Diffraction ◽

Nano Silica ◽

High Volume Fly Ash ◽

Class F Fly Ash

This paper evaluates the effect of Ultrafine Fly Ash (UFFA) and nanoSilica (NS) on compressive strength of high volume fly ash (HVFA) mortar at 7 days and 28 days. Three series of mortar mixes are considered in the first part of this study. In the first series the effect of high content of class F fly ash as partial replacement of cement at 40, 50 and 60% (by wt.) are considered. While in the second and third series, the UFFA and NS are used as partial replacement of cement at 5%, 8%, 10%, 12% and 15% and 1%, 2%, 4%, 6% and 8% (by wt.) of cement, respectively. The UFFA and the NS content which exhibited highest compressive strength in the above series are used in the second part where their effects on the compressive strength of HVFA mortars are evaluated. Results show that the mortar containing 10% UFFA as partial replacement of cement exhibited the highest compressive strength at both 7 and 28 days among all UFFA contents. Similarly, the mortar containing 2% NS as partial replacement of cement exhibited the best performance. Interestingly, the use of UFFA in HVFA mortars did not improve the compressive strength. However, the use of 2% and 4% NS showed improvement in the compressive strength of HVFA mortar containing 40% and 50% fly ash at both ages. The effects of NS and UFFA on the hydration and strength development of HVFA mortar is also evaluated through X-Ray Diffraction (XRD) test. Results also show that the UFFA and NS can significantly reduce the calcium hydroxide (CH) in HVFA mortars.

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