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Article
Publication date: 4 June 2021

Niragi Dave, Ramesh Guduru, Anil Kumar Misra and Anil Kumar Sharma

The consumption of supplementary cementitious materials (SCMs) has increased enormously in the construction industry. These SCMs are often waste materials or industrial…

Abstract

Purpose

The consumption of supplementary cementitious materials (SCMs) has increased enormously in the construction industry. These SCMs are often waste materials or industrial by-products. This study aims to investigate the bond strength using reinforcing bars in Normal Strength Concrete (M20 grade) and High Strength Concrete (M40 grade), developed using SCMs and data was compared with concrete prepared with ordinary portland cement (OPC). The findings of the study will help in reducing the dependency on OPC and promote the utilization of waste materials in Construction.

Design/methodology/approach

In the present study, the bond behavior between the steel bars and the concrete was investigated in controlled, binary and quaternary concretes of M20 and M40 grades. Following the conventional procedures, samples were prepared and mechanical tests conducted (as per IS:2770–1 code for M20 and M40 grade concrete structures), which showed an improvement in the bond strength depending on the extent of overall calcium and silica content in these composite mixtures, and thus reflected the importance of vigilant utilization of used industrial waste in the OPC as a replacement without exceeding silica content beyond certain percentages for enhanced structural properties.

Findings

Experimental evaluation of bond behavior results showed a brittle nature for the controlled (OPC) concrete mixtures. While binary and quaternary concrete was able to resist the load-carrying capacity under large deformations and prevented the split cracking and disintegration of the concretes. Among different variations in the chemistry, for both M20 and M40 grades, the maximum bond strengths were observed for 10% Metakaolin + 10% Silica Fume + 30% Fly Ash + 50% OPC composition and this could be attributed to the fineness of the additives, better packing and enhanced calcium silicate hydrate (C-S-H).

Originality/value

Quaternary concrete may be a future option in place of OPC concrete. Very limited data is available related to the bond strength of quaternary concrete. Experimental analysis on quaternary concrete shows that its use in construction can reduce both construction cost and a burden on natural raw materials used to make OPC.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 28 May 2021

Manjunatha M. and Rakshith S.G.K.

Waste foundry sand (WFS) is a by-product of the metal casting industries and is used for land filling purposes. Disposing of waste creates problems to environment and…

Abstract

Purpose

Waste foundry sand (WFS) is a by-product of the metal casting industries and is used for land filling purposes. Disposing of waste creates problems to environment and increases disposal values. To reduce environmental pollutions and solving disposal problems, several authors in worldwide are carried out research work by partial and complete replacing of natural sand with WFS in concrete mixtures. It is found that WFS can be used for production of structural grade concrete. The mechanical characteristics and flexural properties of RC beams has been reviewed in this paper. From this literature review, it has been noticed that there are improvements in concrete strength properties with WFS.

Design/methodology/approach

The results of various properties of concrete have been discussed in this review articles such as compressive strength, split tensile strength, flexural strength, modulus of elasticity, SEM micro-structures and flexural strength properties of RC beams.

Findings

From the literature review, it is found that there is gap of research on flexural behavior of reinforced concrete beam with WFS.

Originality/value

By using WFS effectively, the environmental pollutions and dumping of waste can be reduced. WFS can be successfully used in structural concrete members.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 2 June 2021

Pritish Gupta Quedou, Eric Wirquin and Chandradeo Bokhoree

The purpose of this paper is to investigate the potential use of construction and demolition waste materials (C&DWM) as an alternative for natural fine aggregates (NFA)…

Abstract

Purpose

The purpose of this paper is to investigate the potential use of construction and demolition waste materials (C&DWM) as an alternative for natural fine aggregates (NFA), in view to solve the disposal problems caused due to landfills. In addition, to evaluate its suitability as a sustainable material, mechanical and durability properties have been performed on different proportions of concrete blending and the results recorded were compared with the reference concrete values.

Design/methodology/approach

In this research, the NFA were replaced at the proportion of 25%, 50%, 75% and 100% of C&DWM with a constant slump range of 130 mm–150 mm. This parameter will assess the consistency of the fresh concrete during transportation process. The characteristics of the end product was evaluated through various tests conducted on hardened concrete samples, namely, compressive strength, flexural strength, depth of penetration of water under pressure, rapid chloride penetration test, carbonation test and ultrasonic pulse velocity (UPV) test. All results recorded were compared with the reference concrete values.

Findings

The results demonstrated that the use of C&DWM in concrete portrayed prospective characteristics that could eventually change the concept of sustainable concrete. It was noted that the compressive and flexural strength decreased with the addition of C&DWM, but nevertheless, a continuous increase in strength was observed with an increase in curing period. Moreover, the increase in rapid chloride penetration and decrease in UPV over time period suggested that the concrete structure has improved in terms of compactness, thus giving rise to a less permeable concrete. The mechanical tests showed little discrepancies in the final results when compared to reference concrete. Therefore, it is opined that C&DWM can be used effectively in concrete.

Originality/value

This study explores the possible utilisation of C&DWM as a suitable surrogative materials in concrete in a practical perspective, where the slump parameter will be kept constant throughout the experimental process. Moreover, research on this method is very limited and is yet to be elaborated in-depth. This approach will encourage the use of C&DWM in the construction sector and in the same time minimise the disposal problems caused due to in landfills.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 14 June 2021

Haiwei Zhu, Hongfa Yu, Haiyan Ma, Bo Da and Qiquan Mei

The purpose of this paper is to compare the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine…

Abstract

Purpose

The purpose of this paper is to compare the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments and ultimately to provide basis and recommendations for the durability design of reinforced concrete (RC) structures.

Design/methodology/approach

Slag concrete specimens mixed with four kinds of rust inhibitors and coated with four kinds of surface strengthening materials were corroded by seawater exposure for 365 days, and the key parameters of chloride ion diffusion were obtained by testing. Then a new service life prediction model, based on the modified model for chloride ion diffusion and reliability theory, was applied to analyze the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments.

Findings

Rust inhibitors and surface strengthening materials can effectively extend the service life of RC structures through different effects on chloride ion diffusion behavior. The effects of rust inhibitors and surface strengthening materials on the service life extension of RC structures adhered to the following trend: silane material > cement-based permeable crystalline waterproof material > hydrophobic plug compound > spray polyurea elastomer > water-based permeable crystalline waterproof material > calcium nitrite > preservative > amino-alcohol composite.

Originality/value

Using a new method for predicting the service life of RC structures, the attenuation law of the service life of RC structures under the action of rust inhibitors and surface strengthening materials in tropical marine environments is obtained.

Details

Anti-Corrosion Methods and Materials, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 11 June 2021

Jichang Wang and Xiaoming Guo

A mesoscopic phase field (PF) model is proposed to simulate the meso-failure process of lightweight concrete.

Abstract

Purpose

A mesoscopic phase field (PF) model is proposed to simulate the meso-failure process of lightweight concrete.

Design/methodology/approach

The PF damage model is applied to the meso-failure process of lightweight concrete through the ABAQUS subroutine user-defined element (UEL). And the improved staggered iteration scheme with a one-pass procedure is used to alternately solve the coupling equations.

Findings

These examples clearly show that the crack initiation of the lightweight concrete specimens mainly occurs in the ceramsite aggregates with weak strength, especially in the larger aggregates. The crack propagation paths of the specimens with the same volume fraction of light aggregates are completely different, but the crack propagation paths all pass through the ceramsite aggregates near the cracks. The results also showed that with the increase in the volume fractions of the aggregates, the slope and the peak loads of the force-deflection (F-d) curves gradually decrease, the load-bearing capacity of the lightweight concrete specimens decreases, and crack branching and coalescence are less likely during crack propagation.

Originality/value

The mesostructures with a mortar matrix, aggregates and an interfacial transition zone (ITZ) are generated by an automatic generation and placement program, thus incorporating the typical three-phase characteristics of lightweight concrete into the PF model.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 23 January 2020

Uchechi G. Eziefula, Hyginus E. Opara and Bennett I. Eziefula

This paper aims to investigate the 28-day compressive strength of concrete produced with aggregates from different sources.

Abstract

Purpose

This paper aims to investigate the 28-day compressive strength of concrete produced with aggregates from different sources.

Design/methodology/approach

Coarse aggregates were crushed granite and natural local stones mined from Umunneochi, Lokpa and Uturu, Isuakwato, respectively, in Abia State, Nigeria. Fine aggregate (river sand) and another coarse aggregate (river stone) were dredged from Otammiri River in Owerri, Imo State, Nigeria. The nominal mix ratios were 1:1:2, 1:2:4 and 1:3:6, whereas the respective water–cement ratios were 0.45, 0.5, 0.55 and 0.6.

Findings

The compressive strength of granite concrete, river stone concrete and local stone concrete ranged 17.79-38.13, 15.37-34.57 and 14.17-31.96 N/mm2, respectively. Compressive strength was found to increase with decreasing water–cement ratio and increasing cement content.

Practical implications

Granite concrete should be used in reinforced-concrete construction, especially when a cube compressive strength of 30 N/mm2 or higher is required.

Originality/value

Granite concrete exceeded the target compressive strength for all the concrete specimens, whereas river stone concrete and local stone concrete failed to achieve the target strength for some mix proportions and water–cement ratios.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 5
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 19 December 2019

Huijun Wu

The purpose of this paper is to research the hardened properties of non-dispersible concrete in seawater environment, especially in seawater environment.

Abstract

Purpose

The purpose of this paper is to research the hardened properties of non-dispersible concrete in seawater environment, especially in seawater environment.

Design/methodology/approach

The main approach is according to the experiment.

Findings

The findings of this paper are: first, because of the washing effect of water, the strength of underwater non-dispersible concrete is lower than that of terrestrial concrete. Second, the strength of non-dispersible underwater concrete with silica fume increases remarkably at different ages. Third, underwater non-dispersible concrete does not produce new products when it is formed and cured in seawater.

Originality/value

In this paper, underwater non-dispersible concrete is formed and maintained on land, freshwater and seawater by underwater pouring method. The working performance, mechanical properties and durability of underwater non-dispersible concrete mixtures after hardening are tested.

Details

International Journal of Structural Integrity, vol. 11 no. 6
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 12 November 2019

Wu Huijun, Zhan Diao and Kaizuo Fan

The purpose of this paper is to focus on the durability of underwater non-dispersible concrete in seawater environment.

Abstract

Purpose

The purpose of this paper is to focus on the durability of underwater non-dispersible concrete in seawater environment.

Design/methodology/approach

In this paper, ten groups of underwater non-dispersible concrete mixtures were designed, and the anti-dispersibility and fluidity of the mixtures were tested.

Findings

The durability test analysis shows that different pouring methods have different effects on the durability of concrete. The durability of concrete poured on land is better than that poured in water. Different mineral admixtures have different effects on the durability of concrete: the frost resistance of the underwater non-dispersible concrete specimens with silica fume is the best; the impermeability and chloride ion permeability of the non-dispersible underwater concrete specimens with waterproofing agent are the best; and the alternation of wetting and drying has adverse effects on the durability indexes of the non-dispersible underwater concrete.

Originality/value

The durability of underwater non-dispersible concrete is tested and the results can be used for reference in engineering practice.

Details

International Journal of Structural Integrity, vol. 11 no. 3
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 1 June 2020

Hakas Prayuda, Fanny Monika and Martyana Dwi Cahyati

This study aims to discuss the results of fresh properties and compressive strength of self-compacting concrete using ingredients added red brick powder as a fine…

Abstract

Purpose

This study aims to discuss the results of fresh properties and compressive strength of self-compacting concrete using ingredients added red brick powder as a fine aggregate substitute. The results of the study were compared with the properties of fresh properties and compressive strength with ingredients added by rice husk ash, which is also a fine aggregate substitute. In addition, the initial compressive strength of each of these variations was also examined to accelerate the completion time of construction projects using self-compacting concrete.

Design/methodology/approach

This research was conducted in a laboratory by testing the characteristics of fresh and hardened properties of self-compacting concrete.

Findings

Fresh properties testing is carried out in the form of V-funnel, flow table, J-ring and L-box where all specimens produce quite varied flow rates. Compressive strength was estimated at ages 3, 7, 14 and 28 days with cylindrical specimens with a diameter of 150 mm and a height of 300 mm. The variation of fine aggregate substitutes used is 20, 40 and 60 per cent.

Originality/value

From the results of the compressive strength, it can be concluded that the added material is categorized as self-compacting concrete with high initial compressive strength, while at 28 days, the compressive strength test results are categorized as high-strength self-compacting concrete.

Details

World Journal of Engineering, vol. 17 no. 4
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 6 May 2021

Pierre van Tonder and Malcolm Shaun Low

There is an increase in greenhouse gasses and global climate change is frequently reported on. What can be done? Certainly to try and reduce the carbon footprint, which is…

Abstract

Purpose

There is an increase in greenhouse gasses and global climate change is frequently reported on. What can be done? Certainly to try and reduce the carbon footprint, which is not a new topic, by encouraging applications and activities for concrete during its lifetime (Portland Cement Association, 2019). This study aims to focus on introducing CO2 to normal and fly ash concrete and thus investigating the effect on the carbon footprint of the samples and the effectiveness of the CO2 introduction methods, namely, carbonated water addition during the mixing process and by means of an infusion pipe directly into the concrete when the samples are casted and have been casted.

Design/methodology/approach

The feasibility of carbon dioxide storage within concrete is determined by investigating the effects of introduced carbon dioxide into concrete samples and the effectiveness of the concrete at storing carbon dioxide. The concrete was mixed in a 1:3:3 ratio for the OPC or blended 52.5 R cement:sand:stone (22 mm) with a 28 day strength of 50 MPa. Samples were also prepared containing low-grade fly ash cement contents ranging from 15% to 60%. CO2 was introduced to the concrete via carbonated mixing water and an infusion pipe system directly to the hardening concrete cubes. In total, 16 g CO2 bicycle carbon dioxide inflators and valve system were used to infuse the concrete over a period of a week until the canister was emptied with valve release on the lowest setting. A compression test was carried out to determine the strength of the concrete cubes with, and without, the introduction of carbon dioxide. Results were also obtained using a scanning electron microscope (SEM) and energy dispersive x-ray spectrometer (EDS) to determine how the carbon dioxide changed the microscopic composition and chemical composition of the concrete. A microcontroller with carbon dioxide sensors was used to gather carbon dioxide emission data for a period of three months.

Findings

The compressive strength tests show by introducing carbon dioxide to the concrete, the compressive strength has increased by as much as 13.86% as expected from the literature. Furthermore, by infusing carbon dioxide with the fly ash blended cement, will give a higher strength compared to the control with ordinary portland cement. This correlates to an overall reduction in cost for the structure. The optimal fly ash content for the control with minimal strength degradation is 30%. Where the optimal fly ash content for the concrete with carbon dioxide stored within, is 45%. The SEM analysis showed the concrete with sequestered carbon dioxide has significantly more calcium silicate hydrate (C-S-H) gel formation, thus the strength increase. Furthermore, the carbon dioxide emission test showed the concrete with infused carbon dioxide stores carbon dioxide more efficiently compared to the control sample. With the data showing the infused sample releases 11.19% less carbon dioxide compared to the control sample. However, the carbonated water sample releases 20.9% more carbon dioxide when compared to the control sample. Thus the introduction of carbon dioxide by means of infusion is more effective.

Practical implications

This is a practical pilot investigation of carbon dioxide introduction via two methods, one being infusion of CO2 into normal concrete and fly ash concrete and two, mixing normal and fly ash concrete with carbonated water. These results show, cheaper cement can be used to achieve equivalent or better strength. This can help in the reduction of the construction industry’s carbon footprint.

Originality/value

By reducing the construction industry’s carbon footprint with this research results, a saving can not only be made financially in the construction industry, but this will help to preserve our environment for future generations.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

Keywords

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