Advancements in Properties of Cement Containing Pulverised Fly Ash and Nanomaterials by Blending and Ultrasonication Method (Review - Part I)

2018 ◽  
Vol 19 ◽  
pp. 1-11 ◽  
Author(s):  
Mehmet Serkan Kirgiz

This review research aims to discuss the results obtained researches on cement containing pure cement, pulverised fly ash, and nanoparticles, in order for eliminating negative side effects underlie the substitution of by–products for pure Portland cement. Nanoparticles (NP) used in these researches are nanoTiO2, nanoSiO2, nanoCaCO3, fibers of carbon nano tube (CNT), nanolimestone (nanoCaCO3), nanoZrO2, nanoclays, and nanometakaolin (nMK) for improving properties of cement systems. Published manuscripts explains two methods regarding on the usage of nanoparticles for cement system: blending and ultrasonication for dispersion of nanoparticles. However, differences between blending and ultrasonication methods suggested by various researchers are also discussed. Experiments reported these papers include the water demand, the density, the setting–times, the heat of hydration, the fluidity, the compressive strength and the flexural strength. According to these results, nanoparticles increase the water demand and heat of hydration of cement; it decreases the density and fluidity for cement mortars, evidently. The most effective nanoparticles on early compressive and flexural strengths are fibers of carbon nano tube and nanoCaCO3. These papers also point effects of these nanoparticles on the strength gain of cement. This review paper inform us until Effect of nanomaterial on water demand and density section in this Part I. Second part of this review paper will explain Hydration properties of Portland pulverised fly ash cement section, Effect of nanomaterial on setting–time section, Effect of nanomaterial on heat of hydration section, Strength gain mechanisms for hardened Portland pulverised fly ash cement paste and mortar section, Effect of nanomaterial on compressive strength section, Effect of nanomaterial on flexural strength (Bending) section, and Conclusion section.

2019 ◽  
Vol 24 ◽  
pp. 37-44 ◽  
Author(s):  
Mehmet Serkan Kirgiz

The second part of this review paper will explain Hydration properties of Portland pulverised fly ash cement section, Effect of nanomaterial on setting–time section, Effect of nanomaterial on heat of hydration section, Strength gain mechanisms for hardened Portland pulverised fly ash cement paste and mortar section, Effect of nanomaterial on compressive strength section, Effect of nanomaterial on flexural strength (Bending) section, and Conclusion section. Experiments reported include the setting–times, the heat of hydration, the compressive strength gain, and the flexural strength gain in the current article. According to the result, nanoparticles, especially the GNP, increase the heat of hydration of cement, and accelerate the time of setting evidently, both initial and final setting-time. The most effective nanoparticle on early compressive strength gain and flexural strength gain is the GNP. The article also points the effects of the nanoparticles on the strength gain of cement comprehensively. Consequently, the prominent cement technology can use the nanoparticles dispersed in liquid by ultrasonication method to increase the properties of cement based materials effectively.


Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3344 ◽  
Author(s):  
Zhiyuan Zhou ◽  
Massoud Sofi ◽  
Elisa Lumantarna ◽  
Rackel San Nicolas ◽  
Gideon Hadi Kusuma ◽  
...  

To address sustainability issues by facilitating the use of high-volume fly ash (HVFA) concrete in industry, this paper investigates the early age hydration properties of HVFA binders in concrete and the correlation between hydration properties and compressive strengths of the cement pastes. A new method of calculating the chemically bound water of HVFA binders was used and validated. Fly ash (FA) types used in this study were sourced from Indonesia and Australia for comparison. The water to binder (w/b) ratio was 0.4 and FA replacement levels were 40%, 50% and 60% by weight. Isothermal calorimetry tests were conducted to study the heat of hydration which was further converted to the adiabatic temperature rise. Thermo-gravimetric analysis (TGA) was employed to explore the chemically bound water (WB) of the binders. The results showed that Australian FA pastes had higher heat of hydration, adiabatic temperature rise, WB and compressive strength compared to Indonesian FA pastes. The new method of calculating chemically bound water can be successfully applied to HVFA binders. Linear correlation could be found between the WB and compressive strength.


Author(s):  
Vu-An Tran

This research investigates the physical and mechanical properties of mortar incorporating fly ash (FA), which is by-product of Duyen Hai thermal power plant. Six mixtures of mortar are produced with FA at level of 0%, 10%, 20%, 30%, 40%, and 50% (by volume) as cement replacement and at water-to-binder (W/B) of 0.5. The flow, density, compressive strength, flexural strength, and water absorption tests are made under relevant standard in this study. The results have shown that the higher FA content increases the flow of mortar but significantly decreases the density of mixtures. The water absorption and setting time increases as the samples incorporating FA. Compressive strength of specimen with 10% FA is approximately equal to control specimen at the 91-day age. The flexural strength of specimen ranges from 7.97 MPa to 8.94 MPa at the 91-day age with the best result for samples containing 10% and 20% FA.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4204 ◽  
Author(s):  
Wei-Ting Lin ◽  
Kae-Long Lin ◽  
Kailun Chen ◽  
Kinga Korniejenko ◽  
Marek Hebda ◽  
...  

Recently, many people around the world have been concerned with environmental protection and sustainability. The goal of various countries’ research has been focused on how to regenerate existing resources. Circulation fluidized bed combustion (CFBC) technology is one of the emerging combustion technologies for electricity generation and produces more than 800,000 tons of CFBC fly ash (CFA) per year for combustion. CFA has been widely applied in cement additive, new building materials and cement-based materials. The goal of this study was to discuss the engineering properties of roller-compacted concrete containing CFA. Test subjects included compressive strength, flexural strength, absorption, setting time, unit weight, sulfate resistance, SEM microscopic observations and XRD ingredient analysis. Test results indicate the following: (1) using CFA as a substitute of fine aggregates up to 10 wt.% would improve the development of later flexural strength; (2) the increases in pre-pressure would increase the compressive strength and unit weight and decrease absorption; (3) using CFA would reduce the initial setting time by 30%–60% and reduce the final setting time by 16%–20%; (4) using CFA would reduce the absorption; (5) using CFA would reduce the unit weight by 0.5%–2.8%, and the increases in pre-pressure would increase the unit weight by about 0.9%–2.1%; (6) CaO in CFA helps to improve sulfate resistance; (7) scanning electron microscopy (SEM) observation shows that the increases in pre-pressure would reduce the pores; and (8) X-ray diffraction (XRD) analysis shows that the inclusion of CFA would increase the content of Ca(OH)2 in concrete.


1984 ◽  
Vol 43 ◽  
Author(s):  
Mark D. Baker ◽  
Joakim G. Laguros

AbstractThe setting and strength gaining process of PC concrete containing Class C high lime fly ash were related to the reaction products identified using XRD and SEM. Four fly ash concrete mixes (20, 30, 40, and 50 percent replacement of cement by fly ash) and similar paste mixes were compared to control mixes for curing periods up to one year. Setting time and early compressive strength were adversely affected by the addition of fly ash. Beyond one week all of the fly ash concrete mixes gained strength at a faster rate than the corresponding control mixes. XRD studies suggest that the retardation mechanism may be associated with the high levels of ettringite formed early in the hydration process and its conversion to monosulfoaluminate. A decrease in the level of calcium hydroxide, typical of pozzolanic activity, was not in evidence. SEM micrographs of fly ash spheres in concrete at the various stages of hydration reveal an intricate crystal framework. A simple heat of hydration test is presented which helps explain the strength gains observed.


Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2515
Author(s):  
Toon Nongnuang ◽  
Peerapong Jitsangiam ◽  
Ubolluk Rattanasak ◽  
Weerachart Tangchirapat ◽  
Teewara Suwan ◽  
...  

Geopolymer (GP) has been applied as an environmentally-friendly construction material in recent years. Many pozzolanic wastes, such as fly ash (FA) and bottom ash, are commonly used as source materials for synthesizing geopolymer. Nonetheless, many non-pozzolanic wastes are often applied in the field of civil engineering, including waste iron powder (WIP). WIPs are massively produced as by-products from iron and steel industries, and the production rate increases every year. As an iron-based material, WIP has properties of heat induction and restoration, which can enhance the heat curing process of GP. Therefore, this study aimed to utilize WIP in high-calcium FA geopolymer to develop a new type of geopolymer and examine its properties compared to the conventional geopolymer. Scanning electron microscopy and X-ray diffraction were performed on the geopolymers. Mechanical properties, including compressive strength and flexural strength, were also determined. In addition, setting time and temperature monitoring during the heat curing process were carried out. The results indicated that the addition of WIP in FA geopolymer decreased the compressive strength, owing to the formation of tetrahydroxoferrate (II) sodium or Na2[Fe(OH)4]. However, a significant increase in the flexural strength of GP with WIP addition was detected. A flexural strength of 8.5 MPa was achieved by a 28-day sample with 20% of WIP addition, nearly three times higher than that of control.


2021 ◽  
Author(s):  
M. Indhumathi Anbarasan ◽  
S.R. Sanjaiyan ◽  
S. Nagan Soundarapandiyan

Geopolymer concrete (GPC) has significant potential as a more sustainable alternative for ordinary Portland cement concrete. GPC had been introduced to reduce carbon footprints and thereby safeguarding environment. This emerging eco friendly construction product finds majority of its application in precast and prefabricated structures due to the special curing conditions required. Sustained research efforts are being taken to make the product suitable for in situ applications. The developed technology will certainly address the issues of huge energy consumption as well reduce water use which is becoming scarce nowadays. Ground Granulated Blast Furnace Slag (GGBS) a by-product of iron industries in combination with fly ash has proved to give enhanced strength, durability as well reduced setting time. This study investigates the effect of GGBS as partial replacement of fly ash in the manufacture of GPC. Cube and cylindrical specimens were cast and subjected to ambient curing as well to alternate wetting-drying cycles. The 28 day compressive strength, split tensile strength, flexural strength and density of GPC specimens were found. The study revealed increase in compressive strength, split tensile strength, density as well flexural strength up to 40 percent replacement of fly ash by GGBS.


Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5406
Author(s):  
Christian Ramadji ◽  
Adamah Messan ◽  
Elodie Prud’Homme

This study explored the pozzolanic reactivity of granite powder (GP) and its influence on the microstructure of cement paste. An analysis of the physical properties (water demand, setting time, heat of hydration and total shrinkage), compressive strength and durability indicators (water absorption, porosity, acid attack and chloride ions diffusion) was carried out on mortar containing 10%, 15% and 20% of GP as partial substitution to cement (CEM I 42.5 R) in the short and long term. The results showed that the GP does not exhibit pozzolanic reactivity and that it reduces the heat of hydration. Water demand and setting time were not affected by the GP. The compressive strength decreases with increasing the content of GP; but in the long term, the compressive strength was not affected for 10% GP substitution. The presence of granite powder in mortar induces an increase in porosity, which led to an increase in the diffusion properties of fluids (capillary water absorption and chloride ions diffusion).


2020 ◽  
Vol 322 ◽  
pp. 01003
Author(s):  
Wei-Ting Lin ◽  
An Cheng ◽  
Michał Łach ◽  
Krzysztof Miernik ◽  
Kinga Korniejenko

This study aims to investigate the binding properties of co-fired fly ash (CFFA) in paste and mortar specimens. Paste specimens containing various CFFA proportions (25%, 50%, 75%, 100% by weight of cement) were conducted and evaluated using setting time tests, water demand tests and compressive strength tests. Mortar specimens containing various CFFA and Pulverised coal fly ash (PCFA) proportions (10%, 20%, 30% by weight of cement) were also conducted and compared with regard to flowability and compressive strength. The test results indicated that the water demand increased as the amount of CFFA replacement increased on the flow level at 110±3%; this is due to the higher ignition loss (L.O.I.). Higher L.O.I. values mean that there are more unburned carbon particles in the CFFA and that most of these carbon particles are porous. The compressive strength of mortar specimens decreased as the amount of CFFA replacement increased. Compared to the chemical compositions of cement (C3S, C2S), the main components of CFFA (Ca(OH)2, CaCO3, CaO) have lower crystalline strength and compactness. Therefore, the higher amount of CFFA replacement would inevitably cause a reduction of the cement contents of specimens, thereby reducing the compressive strength of the mortar specimens. Thus, an appropriate amount of superplasticiser and CFFA replacement in the mixture is useful with regard to the binding properties of cementitious materials.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2073
Author(s):  
Qiubai Deng ◽  
Zhenyu Lai ◽  
Rui Xiao ◽  
Jie Wu ◽  
Mengliang Liu ◽  
...  

Waste glass is a bulk solid waste, and its utilization is of great consequence for environmental protection; the application of waste glass to magnesium phosphate cement can also play a prominent role in its recycling. The purpose of this study is to evaluate the effect of glass powder (GP) on the mechanical and working properties of magnesium potassium phosphate cement (MKPC). Moreover, a 40mm × 40mm × 40mm mold was used in this experiment, the workability, setting time, strength, hydration heat release, porosity, and microstructure of the specimens were evaluated. The results indicated that the addition of glass powder prolonged the setting time of MKPC, reduced the workability of the matrix, and effectively lowered the hydration heat of the MKPC. Compared to an M/P ratio (MgO/KH2PO4 mass ratio) of 1:1, the workability of the MKPC with M/P ratios of 2:1 and 3:1 was reduced by 1% and 2.1%, respectively, and the peak hydration temperatures were reduced by 0.5% and 14.6%, respectively. The compressive strength of MKPC increased with an increase in the glass powder content at the M/P ratio of 1:1, and the addition of glass powder reduced the porosity of the matrix, effectively increased the yield of struvite-K, and affected the morphology of the hydration products. With an increase in the M/P ratio, the struvite-K content decreased, many tiny pores were more prevalent on the surface of the matrix, and the bonding integrity between the MKPC was weakened, thereby reducing the compressive strength of the matrix. At less than 40 wt.% glass powder content, the performance of MKPC improved at an M/P ratio of 1:1. In general, the addition of glass powders improved the mechanical properties of MKPC and reduced the heat of hydration.


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