Study of Hydration and Microstructure of Mortar Containing Coral Sand Powder Blended with SCMs

The utilization of coral waste is an economical way of using concrete in coastal and offshore constructions. Coral waste with more than 96% CaCO3 can be ground to fines and combined with supplementary cementitious materials (SCMs) such as fly ash, silica fume, granulated blast furnace slag in replacing Portland cement to promote the properties of cement concrete. The effects of coral sand powder (CSP) compared to limestone powder (LSP) blended with SCMs on hydration and microstructure of mortar were investigated. The result shows CSP has higher activity than LSP when participating in the chemical reaction. The chemical effect among CSP, SCMs, and ordinary Portland cement (OPC) results in the appearance of the third hydration peak, facilitating the production of carboaluminate. CSP-SCMs mortar has smaller interconnected pores on account of the porous character of CSP as well as the filler and chemical effect. The dilution effect of CSP leads to the reduction of compressive strength of OPC-CSP and OPC-CSP-SCMs mortars. The synergic effects of CSP with slag and silica fume facilitate the development of compressive strength and lead to a compacted isolation and transfer zone (ITZ) in mortar.

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Durability of Sustainable Self-Consolidating Concrete

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.765.285 ◽

2018 ◽

Vol 765 ◽

pp. 285-289

Author(s):

Osama Ahmed Mohamed ◽

Waddah Al Hawat ◽

Omar Fawwaz Najm

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Silica Fume ◽

Cementitious Materials ◽

Chloride Penetration ◽

Supplementary Cementitious Materials ◽

Test Results ◽

Self Consolidating Concrete ◽

Human Footprint ◽

Granulated Blast Furnace Slag

Supplementary cementitious materials such as fly ash, silica fume and ground granulated blast furnace slag (GGBS) have been used widely to partially replace cement in producing self-consolidating concrete (SCC). The production of cement is associated with emission of significant amounts of CO2 and increases the human footprint on the environment. Fly ash, silica fume, and GGBS are recycled industrial by-products that also impart favorable fresh and hardened properties on concrete. This study aims to assess the effect of the amounts of fly ash and silica fume on strength and chloride penetration resistance of concrete. Rapid Chloride Penetration Test (RCPT) was used to assess the ability of SCC to resist ingress of chlorides into concrete. SCC mixes with different dosages of fly ash and silica fume were developed and tested at different curing ages. Test results showed that replacing 20% of cement with fly ash produced the highest compressive strength of 67.96 MPa among all fly ash-cement binary mixes. Results also showed that replacing15% of cement with silica fume produced the highest compressive strength of 95.3 MPa among fly ash-cement binary mixes. Using fly ash and silica fume consistently increased the concrete resistance to chloride penetration at the early ages. Silica fume at all dosages results in low or very low levels of chloride penetration at all curing ages of concrete.

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The properties of slag-silica fume ternary blended mortar with quarry dust

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.1.2020.19.0504 ◽

2020 ◽

Vol 14 (1) ◽

pp. 6443-6451 ◽

Cited By ~ 3

Author(s):

Chow Wee Kang ◽

Cheah Chee Ban ◽

Oo Chuan Wei ◽

Part Wei Ken ◽

Leow Khang Heng

Keyword(s):

Portland Cement ◽

Silica Fume ◽

Drying Shrinkage ◽

High Strength ◽

Total Porosity ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Fine Aggregate ◽

Granulated Blast Furnace Slag ◽

Quarry Dust

High carbon emissions of manufactured Portland cement in the concrete industry have incurred several interests in reducing the use of Portland cement by partially replacing it with supplementary cementitious materials. Most of which, are by-products from other manufacturing industries. Hence, the main purpose of this study is to investigate the effects of different combinations of ternary blended mortars incorporating supplementary cementitious materials such as Ground Granulated Blast Furnace Slag (GGBS) and Densified Silica Fume (DSF). In this study, mortars were prepared with 100% quarry dust and GGBS was replaced with DSF at 2% step increments up to 16% at a w/b ratio of 0.24. At the same time OPC content was fixed at 50%. The compressive and flexural strength, drying shrinkage, and porosity of mortars were all tested. The results indicated that the increasing DSF content increases; GGBS reduces the superplasticizer dosage for the desired workability of the mortar. The utilization GGBS and DSF has improved the performances ternary blended mortar incorporating quarry dust as a fine aggregate in terms of mechanical strength, drying shrinkage and total porosity tested. The high strength ternary blended mortar incorporating GGBS and DSF exhibited optimum mechanical and durability performance at the OPC:GGBS:DSF ratio of 50:38:12.

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Utilization of tailings in cement and concrete: A review

Science and Engineering of Composite Materials ◽

10.1515/secm-2019-0029 ◽

2019 ◽

Vol 26 (1) ◽

pp. 449-464 ◽

Cited By ~ 3

Author(s):

Mifeng Gou ◽

Longfei Zhou ◽

Nathalene Wei Ying Then

Keyword(s):

Compressive Strength ◽

Cementitious Materials ◽

Solid Wastes ◽

Supplementary Cementitious Materials ◽

Cement Clinker ◽

Fine Aggregate ◽

Granulated Blast Furnace Slag ◽

Fine Aggregates ◽

Compressive Strength Of Concrete ◽

Cement And Concrete

AbstractOne of the advantages of cement and the cement concrete industry in sustainability is the ability to utilize large amounts of industrial solid wastes such as fly ash and ground granulated blast furnace slag. Tailings are solid wastes of the ore beneficiation process in the extractive industry and are available in huge amounts in some countries. This paper reviews the potential utilization of tailings as a replacement for fine aggregates, as supplementary cementitious materials (SCMs) in mortar or concrete, and in the production of cement clinker. It was shown in previous research that while tailings had been used as a replacement for both fine aggregate and cement, the workability of mortar or concrete reduced. Also, at a constant water to cement ratio, the compressive strength of concrete increased with the tailings as fine aggregate. However, the compressive strength of concrete decreased as the replacement content of the tailings as SCMs increased, even whentailings were ground into smaller particles. Not much research has been dedicated to the durability of concrete with tailings, but it is beneficial for heavy metals in tailings to stabilize/solidify in concrete. The clinker can be produced by using the tailings, even if the tailings have a low SiO2 content. As a result, the utilization of tailings in cement and concrete will be good for the environment both in the solid waste processing and virgin materials using in the construction industry.

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Current situation with the production and use of supplementary cementitious materials (SCMs) in concrete construction in Canada

Canadian Journal of Civil Engineering ◽

10.1139/l04-109 ◽

2005 ◽

Vol 32 (1) ◽

pp. 129-143 ◽

Cited By ~ 10

Author(s):

Nabil Bouzoubaâ ◽

Benoît Fournier

Keyword(s):

Fly Ash ◽

Silica Fume ◽

Blended Cement ◽

Cementitious Materials ◽

Current Situation ◽

Supplementary Cementitious Materials ◽

Market Demand ◽

Granulated Blast Furnace Slag ◽

The Us ◽

Economic Barriers

The data gathered on the current situation of supplementary cementing materials (SCMs) in Canada have shown that around 524 000, 347 000, and 37 000 t of fly ash, ground granulated blast furnace slag (GGBFS), and silica fume were used in cement and concrete applications in 2001, respectively, which represents 11%, 90%, and 185% of the quantity produced. The remaining 10% of GGBFS produced was used in the US, and 17 000 t of silica fume were imported from the US and Norway to meet market demand. Fly ash appears to be the only material that is underused and that represents a potential for increased use of SCMs in Canada. For the GGBFS, the quantity produced can be increased if the demand increases. This investigation has shown, however, that there are policy, technical, and economic barriers to the increased use of SCMs in Canada. Some solutions were proposed to overcome these barriers and are summarized in the conclusions of the paper.Key words: fly ash, slag, silica fume, concrete, blended cement.

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Utilization of Cementitious Materials with Cold-bonded Artificial Aggregate in Concrete

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a9376.109119 ◽

2019 ◽

Vol 9 (1) ◽

pp. 385-388

Keyword(s):

Compressive Strength ◽

Silica Fume ◽

Lightweight Concrete ◽

Lightweight Aggregate ◽

Cementitious Materials ◽

Lightweight Aggregate Concrete ◽

Optimum Level ◽

Aggregate Concrete ◽

Glass Fibres ◽

Granulated Blast Furnace Slag

This article investigates the slump and compressive strength of artificial lightweight aggregate concrete with Ground Granulated Blast Furnace Slag (GGBFS) and Silica Fume with glass fibres. The increase in usage of cement in the construction industry is a concern for ecological deterioration, in this view; artificial aggregates was manufactured with major amount of fly ash and replacement of cement with various industrial by-products in concrete. An optimum level of GGBFS from 10 to 50% and Silica Fume from 2 to 6% with addition of glass fibres was assessed based on compressive strength values. The compressive strength was conducted for 7 and 28Days of water curing on M30 grade lightweight concrete with constant water to cement ratio as 0.45 and 0.2% of Master Gelenium super plasticizer. The conclusions achieved from the compressive strength of concrete containing GGBFS and Silica Fume was increased as the curing time increases. As a result lightweight aggregate concrete with a cement content of 226 kg/m3 develops 37.3 N/mm2 compressive strength.

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Production of Ultra-High-Performance Concrete with Low Energy Consumption and Carbon Footprint Using Supplementary Cementitious Materials Instead of Silica Fume: A Review

Energies ◽

10.3390/en14248291 ◽

2021 ◽

Vol 14 (24) ◽

pp. 8291

Author(s):

Mays A. Hamad ◽

Mohammed Nasr ◽

Ali Shubbar ◽

Zainab Al-Khafaji ◽

Zainab Al Masoodi ◽

...

Keyword(s):

Energy Consumption ◽

Silica Fume ◽

High Performance ◽

High Performance Concrete ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Ultra High Performance Concrete ◽

Cement Production ◽

Granulated Blast Furnace Slag ◽

The Impact

The increase in cement production as a result of growing demand in the construction sector means an increase in energy consumption and CO2 emissions. These emissions are estimated at 7% of the global production of CO2. Ultra-high-performance concrete (UHPC) has excellent mechanical and durability characteristics. Nevertheless, it is costly and affects the environment due to its high amount of cement, which may reach 800–1000 kg/m3. In order to reduce the cement content, silica fume (SF) was utilized as a partial alternative to cement in the production of UHPC. Nevertheless, SF is very expensive. Therefore, the researchers investigated the use of supplementary cementitious materials cheaper than SF. Very limited review investigates addressed the impact of such materials on different properties of UHPC in comparison to that of SF. Thus, this study aims to summarize the effectiveness of using some common supplementary cementitious materials, including fly ashes (FA), ground granulated blast furnace slag (GGBS), metakaolin (MK) and rice husk ashes (RHA) in the manufacturing of UHPC, and comparing the performance of each material with that of SF. The comparison among these substances was also discussed. It has been found that RHA is considered a successful alternative to SF to produce UHPC with similar or even higher properties than SF. Moreover, FA, GGBS and MK can be utilized in combination with SF (as a partial substitute of SF) as a result of having less pozzolanic activity than SF.

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The effect of Vietnam’s nano-silica on mechanical properties of high-performance concrete

Transport and Communication Science Journal ◽

10.47869/tcsj.72.1.9 ◽

2021 ◽

Vol 72 (1) ◽

pp. 76-83

Author(s):

Lam Le Hong ◽

Lam Dao Duy ◽

Huu Pham Duy

Keyword(s):

Compressive Strength ◽

Silica Fume ◽

High Performance ◽

High Performance Concrete ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Nano Silica ◽

Nano Sio2 ◽

Curing Period ◽

Compressive Strength Test

The demand for High Performance Concrete (HPC) is steadily increasing with massive developments. Conventionally, it is possible to use industrial products such as silica fume (SF), fly ash, as supplementary cementitious materials (SCM), to enhance the attributes of HPC. In recent years, nano-silica (NS) is used as an additive in added mainly to fill up the deviation arises with the addition of SF for HPC. This study aims to optimize the proportion of NS (produced in Vietnam) in the mixture used for fabricating 70 MPa high-performance concrete. SiO2 powder with particle size from 10 to 15 nm were used for mixing. A series of compressive strength test of HPC with nano-SiO2 varied from 0 to 2.8 percent of total of all binders (0%, 1.2%, 2%, 2.8%), and the fixed percentage of silica fume at 8% were proposed. Results show compressive strength increases with the increase of nano-SiO2, but this increase stops after reaching 2%. And at day 28 of the curing period, only concrete mixture containing of 8% silica fume and 2% nano-SiO2, had the highest compressive strength.

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Experimental Studies on Rheological and Durability Properties of Self Compacting Concrete by Using Quatenary Blending

10.29007/81v5 ◽

2018 ◽

Author(s):

Ashika Shah ◽

Indrajit Patel ◽

Jagruti Shah ◽

Gaurav Gohil

Keyword(s):

Compressive Strength ◽

Experimental Studies ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Self Compacting Concrete ◽

Durability Properties ◽

Granulated Blast Furnace Slag ◽

Strength And Durability ◽

Primary Contribution ◽

Furnace Slag

In the production of Self Compacting concrete (SCC), the use of quaternary blend of supplementary cementitious materials (SCM’s) has not found enough applications. For this purpose, an effort has been done to present a mix design for M60 grade and M80 grade SCC with quaternary blending of fly ash(FA), ground granulated blast furnace slag (GGBS), silica fume (SF) in accordance with EFNARC guidelines. Findings: In this study, cement has been replaced with SCM’s from 30% to 50%. Fresh properties of concrete were tested for slump flow, T50 test and U box. The hardened properties of concrete were tested for compressive strength and durability. The tests were performed for 7, 28, 56 and 91 days. The results indicate that the use of quaternary blend has improved the workability, compressive strength and durability properties of specimens than the control specimen. Application: The primary contribution is to fill the congestedreinforcement and increase the durability and life span of the structure.

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Stabilization of Sulfate-Containing Soil by Cementitious Mixtures Mechanical Properties

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1837-02 ◽

2003 ◽

Vol 1837 (1) ◽

pp. 12-19 ◽

Cited By ~ 20

Author(s):

Lan Wang ◽

Amitava Roy ◽

Roger K. Seals ◽

John B. Metcalf

Keyword(s):

Compressive Strength ◽

Portland Cement ◽

Cementitious Materials ◽

Curing Temperature ◽

Type I ◽

Size Fractions ◽

Granulated Blast Furnace Slag ◽

Local Parish ◽

Stabilized Soil ◽

North Louisiana

Winn Rock (CaSO4) gravel from a quarry in Winn Parish in north Louisiana was used extensively as a surface course for local parish roads. Stabilization of these roads with Type I portland cement followed by an overlay of asphaltic concrete resulted in heaving. A study was undertaken to investigate the cause or causes of the expansion as well as to identify an alternate means of stabilization. Specimens of representative soil from the affected area were stabilized in the laboratory using various cementitious materials and were cured using a variety of methods. The mix contained 5% to 20% cementitious material. The cementitious materials were Type I portland cement, lime, and supplementary cementing materials such as granulated blast furnace slag (BFS), Class C fly ash (CFA), silica fume, and an amorphous silica (AS). The unconfined compressive strength of the stabilized soil was determined. The effect of size fractions other than the gravel on the expansion was assessed, and the expansion of the specimens over time was monitored. The cement and BFS mixtures almost doubled the compressive strength of the specimens compared with portland cement alone. The finer size fractions were responsible for expansion. The magnitude of expansion was directly proportional to the amount of Type I portland cement, the amount of available moisture, and the curing temperature. Replacement of a part of the portland cement by BFS significantly reduced the amount of expansion even at the highest moisture content. No expansion was detected when CFA and AS partially replaced the cement.

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Hydration–Strength–Workability–Durability of Binary, Ternary, and Quaternary Composite Pastes

Materials ◽

10.3390/ma15010204 ◽

2021 ◽

Vol 15 (1) ◽

pp. 204

Author(s):

Yi Han ◽

Seokhoon Oh ◽

Xiao-Yong Wang ◽

Run-Sheng Lin

Keyword(s):

Compressive Strength ◽

Cement Paste ◽

Carbon Emissions ◽

Cementitious Materials ◽

Heat Of Hydration ◽

Surface Resistivity ◽

Cement Industry ◽

Supplementary Cementitious Materials ◽

Limestone Powder ◽

Alternative Materials

At present, reducing carbon emissions is an urgent problem that needs to be solved in the cement industry. This study used three mineral admixtures materials: limestone powder (0–10%), metakaolin (0–15%), and fly ash (0–30%). Binary, ternary, and quaternary pastes were prepared, and the specimens’ workability, compressive strength, ultrasonic pulse speed, surface resistivity, and the heat of hydration were studied; X-ray diffraction and attenuated total reflection Fourier transform infrared tests were conducted. In addition, the influence of supplementary cementitious materials on the compressive strength and durability of the blended paste and the sustainable development of the quaternary-blended paste was analyzed. The experimental results are summarized as follows: (1) metakaolin can reduce the workability of cement paste; (2) the addition of alternative materials can promote cement hydration and help improve long-term compressive strength; (3) surface resistivity tests show that adding alternative materials can increase the value of surface resistivity; (4) the quaternary-blended paste can greatly reduce the accumulated heat of hydration; (5) increasing the amount of supplementary cementitious materials can effectively reduce carbon emissions compared with pure cement paste. In summary, the quaternary-blended paste has great advantages in terms of durability and sustainability and has good development prospects.

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