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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: 18 March 2014

N. Anand, G. Arulraj and C. Aravindhan

Development of Self Compacting Concrete (SCC) is considered as one of the most significant development in the construction industry due to its numerous inherited benefits…

Abstract

Development of Self Compacting Concrete (SCC) is considered as one of the most significant development in the construction industry due to its numerous inherited benefits. With the introduction of super-plasticizers and viscosity modifying agents, it is now possible to produce concrete with high fluidity, good cohesiveness which does not require external energy for compaction. The proper understanding of the effects of elevated temperatures on the properties of SCC is necessary to ensure the safety of buildings made with SCC during fire. During the present investigation, an attempt has been made to study the stress-strain behaviour of Normal Compacting Concrete (NCC) and Self Compacting Concrete at a temperature of 900°C. A significant reduction in the Ultimate compressive strength of SCC was observed during this study. The reduction was found to be more for SCC compared to Normal compacting concrete. The reduction in the compressive strength of SCC was found to be 81.5 % for M40 concrete when exposed to 900°C.

Details

Journal of Structural Fire Engineering, vol. 5 no. 1
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 11 July 2019

Ashok Kumar Sahani, Amiya K. Samanta and Dilip K. Singharoy

Present study focuses on scope of developing sustainable heat resistant concrete by adding steel fibre (Sf) and polypropylene fibre (PPf) along with partially replacement…

Abstract

Purpose

Present study focuses on scope of developing sustainable heat resistant concrete by adding steel fibre (Sf) and polypropylene fibre (PPf) along with partially replacement of ordinary portland cement (OPC) and natural fine aggregate with fly ash (FA) and granular blast furnace slag (GBFS). Replacement percentages of FA and GBFS were 40% and 50%, whereas Sf and PPf for fibre-added mixes were 1% by volume of concrete and 0.25% by weight of cement, respectively.

Design/methodology/approach

An experimental work had been carried out to make comparison between control mix (CM), fibre-added sustainable mix (SCMF) and fibre-added control mix (CMF) with reference to weight loss, mechanical strength (compressive, split and flexure) after exposed to room temperature (27°C) to 1000°C at the interval of 200°C for 4 h of heat curing followed by furnace cooling and then natural cooling. Furthermore, microstructural analysis was executed at 27°C, 400°C and 800°C, respectively.

Findings

Colour change and hair line cracks were started to appear at 600°C. Fibre-added control mix and sustainable mix did not exhibit any significant cracks as compared to control mix even at 1000°C. Major losses were occurred at temperature higher than 600°C, loss in compressive strength was about 70% in control mix, while 60% in fibre-added mixes. SCMF exhibited the highest retention of strength with respect to all cases of mechanical strength.

Research limitations/implications

Present study is based on the slow heating condition followed by longer duration of heat curing at target temperature.

Practical implications

Present work can be helpful for the design engineer for assessing the fire deterioration of concrete structure existing near the fire establishment such as furnace and ovens. Building fire (high temperature for short duration) might be the further scope of work.

Originality/value

Concept of incorporating pozzolanic binder and calcareous fine aggregate was adopted to take the advantage pozzolanacity and fire resistivity. To the best of author’s knowledge, there is a scope for fill the research gap in this area.

Details

Journal of Structural Fire Engineering, vol. 10 no. 4
Type: Research Article
ISSN: 2040-2317

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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: 12 October 2010

S. Ghanbarpour, H. Mazaheripour, S.H. Mirmoradi and A. Barari

Self‐compacting concrete (SCC) offers several economic and technical benefits; the use of steel fibers extends its possibilities. Steel fibers bridge cracks, retard their…

Abstract

Purpose

Self‐compacting concrete (SCC) offers several economic and technical benefits; the use of steel fibers extends its possibilities. Steel fibers bridge cracks, retard their propagation, and improve several characteristics and properties of the SCC. The purpose of this paper is to investigate the effects of type and volume fraction of steel fiber on the compressive strength, split tensile strength, flexural strength and modulus of elasticity of steel fiber reinforced self‐compacting concrete (SFRSCC).

Design/methodology/approach

For this purpose, Micro wire and Wave type steel fibers with l/d ratios of 50 were used. Three different fiber volumes were added to concrete mixes at 0.5, 0.75 and 1 per cent by volume of SCC. Six different SFRSCC mixes were prepared. After 28 days of curing, compressive, split and flexural strength and modulus of elasticity were determined.

Findings

It was found that, inclusion of steel fibers significantly affect the split tensile and flexural strength of SCC accordance with type and vf. Besides, mathematical expressions were developed to estimate the flexural, modulus of elasticity and split tensile strength of SFRSCCs regarding of compressive strength.

Originality/value

It was found that inclusion of steel fibers significantly affected the split tensile and flexural strength of SCC accordance with type and f v.

Details

Journal of Engineering, Design and Technology, vol. 8 no. 3
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 14 March 2016

Ya Wei, Francis T.K. Au, Jing Li and Neil C.M. Tsang

This paper aims to understand the structural fire performance of two-way post-tensioned flat slabs, particularly their deformations and load-carrying mechanisms in fire…

Abstract

Purpose

This paper aims to understand the structural fire performance of two-way post-tensioned flat slabs, particularly their deformations and load-carrying mechanisms in fire, and to explore the behaviour of post-tensioned high-strength self-compacting concrete flat slabs with unbonded tendons in fire.

Design/methodology/approach

Four tests of post-tensioned high-strength self-compacting concrete flat slabs were conducted under fire conditions. Numerical modelling using the commercial package ABAQUS was conducted to help interpret the test results.

Findings

Two of the specimens with lower moisture contents demonstrated excellent fire resistance performance, while the others with slightly higher moisture contents experienced severe concrete spalling.

Originality/value

The test results were discussed in respect of thermal profiles, deflections, crack patterns and concrete spalling. The performance of post-tensioned high-strength self-compacting concrete flat slabs with unbonded tendons under fire conditions was better understood.

Details

Journal of Structural Fire Engineering, vol. 7 no. 1
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 18 June 2021

Adithya Tantri, Gopinatha Nayak, Adithya Shenoy and Kiran K. Shetty

This study aims to present the results of an experimental evaluation of low (M30), mid (M40) and high (M50) grade self-compacting concrete (SCC) with three nominal maximum…

Abstract

Purpose

This study aims to present the results of an experimental evaluation of low (M30), mid (M40) and high (M50) grade self-compacting concrete (SCC) with three nominal maximum aggregate sizes (NMAS), namely, 20 mm, 16 mm and 12.5 mm, with Bailey gradation (BG) in comparison with Indian standard gradation (ISG).

Design/methodology/approach

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

Findings

Rheological and mechanical properties of SCC were evaluated in detail and according to the results, a concrete sample containing lower NMAS with BG demonstrated improvement in modulus of elasticity and compressive strength, while improving the rheological properties as well. Meanwhile, SCC demonstrated poor performance in split tensile and flexural strengths with lower NMAS gradations and a direct correlation was evident as the increase in NMAS caused an increase in the strength and vice-versa.

Originality/value

Upon comparison of BG with ISG, it was revealed that BG mixes succeeded to demonstrate superior performance. From the material optimization, rheological and mechanical performance study, it is recommended that BG with NMAS 16 mm can be used for conventional SCC.

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: 30 August 2011

James Sommerville, Nigel Craig and Antoinette Charles

No‐fines concrete (NFC) is an open textured cellular concrete obtained by eliminating either fines or sand from the normal concrete mix. Research in the 1950s showed this…

Abstract

Purpose

No‐fines concrete (NFC) is an open textured cellular concrete obtained by eliminating either fines or sand from the normal concrete mix. Research in the 1950s showed this material to be capable of energy and cement savings and worthy of being seen as a material that would revolutionise the way affordable homes could be built. In today's context, it may be argued that homes built using this material suffer from fuel poverty as a result of their thermal performance characteristics. This paper seeks to discuss the performance characteristics of NFC in social housing by identifying the nature of the material and the influence of pore structure on heat loss through the fabric of the building.

Design/methodology/approach

Exploratory work was carried out to determine the build and performance characteristics of NFC as used in a range of social housing units. The work includes both laboratory tests and site investigations to identify the physical, thermal, visual and quality characteristics of NFC in cores taken from existing housing units in Irvine, Scotland and units cast in the lab.

Findings

The findings from the tests are used to discuss the actual characteristics of NFC and highlight the nature of pores in NFC and, their influence on heat loss through the external fabric.

Practical implications

Identifying the nature of pores in NFC helps provide approaches towards optimising solutions aimed at improving the thermal performance of the building.

Originality/value

This paper is the first to discuss the on‐site build and performance characteristics of NFC and the nature and influence of pores on the thermal performance of NFC.

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Article
Publication date: 17 June 2015

Marija Jelcic Rukavina, Dubravka Bjegovic and Ivan Gabrijel

This paper presents an experimental research on the performance of high-strength selfcompacting concrete (SCC) with different mineral additives after exposure to high…

Abstract

This paper presents an experimental research on the performance of high-strength selfcompacting concrete (SCC) with different mineral additives after exposure to high temperatures of up to 600°C. For this purpose, four SCC mixtures were studied: one reference and three mixtures where the Portland cement was replaced with mineral additive (fly ash, metakaolin and limestone) in certain proportions. After natural cooling in the furnace, compressive strength and static modulus of elasticity were determined and compared to results obtained from other studies and those provided in EN 1992-1-2 and EN 1994-1-2 for normal-vibrated concrete. Additionally, acoustic emission (AE) parameters during compression test of heated and unheated specimens were also obtained which showed good non-destructive tool for identifying exposure temperature of the concrete needed for the assessment of concrete structures after fire.

Details

Journal of Structural Fire Engineering, vol. 6 no. 3
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 19 August 2021

Oliver Bahr

This paper aims to answer two questions. First, are there any differences in the fire performance of columns made of normal and of high-strength concrete? Second, under…

Abstract

Purpose

This paper aims to answer two questions. First, are there any differences in the fire performance of columns made of normal and of high-strength concrete? Second, under which circumstances does the fire design govern the cross-sectional dimensions of concrete columns? Is it feasible to replace columns out of normal strength concrete by more slender high-strength concrete columns?

Design/methodology/approach

The author conducted numerical studies using the finite element code “Infocad” of the German company “Infograph”. The studies included the effect of different parameters on the fire performance of columns out of normal and high-strength concrete, i.e. the load ratio and eccentricity, boundary conditions and times of fire exposure.

Findings

Results from the numerical investigations showed that high-strength concrete columns suffer much more from heating than normal strength concrete columns. This is the outcome of the unfavourable mechanical properties of high-strength concrete at elevated temperatures. Although the relative fire performance of columns out of high-strength concrete is worse than that of columns out of normal strength concrete, initial load reserves are beneficial to achieve even high fire ratings.

Originality/value

Many researchers addressed in experimental and numerical studies the fire performance of columns out of normal and high-strength concrete. A special emphasis was often laid on the spalling of fire-exposed high-strength concrete. However, there are no systematic investigations when the fire design governs the cross-sectional dimensions of high-strength concrete columns. Based on a previous comparison of the relative fire performance of columns out of normal and high-strength concrete, this paper, hence, addresses the question whether there is a reasonable lower limit for the use of these columns. This is an important aspect for designers since there is a tendency to replace columns out of normal strength concrete by columns out of high-strength concrete. Higher concrete strengths allow for smaller cross sections of the columns, and designers may, hence, increase the usable space of buildings.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

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