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1 – 10 of over 1000
Article
Publication date: 11 June 2018

Shubham Raj, Amrendra Kumar Rai and Vasant G. Havanagi

Industrial wastes such as copper slag and fly ash are being generated in tons every year and disposed mainly by land fillings, resulting in wastage of useful land. Copper slag in…

Abstract

Purpose

Industrial wastes such as copper slag and fly ash are being generated in tons every year and disposed mainly by land fillings, resulting in wastage of useful land. Copper slag in itself is a granular cohesionless sand-like material, while fly ash is highly pozzolanic. The purpose of this paper is to investigate copper slag and fly ash mixes with cement as stabilizer for their proper use in road construction.

Design/methodology/approach

Different trial mixes of copper slag and fly ash were tested for obtaining the optimum mix having maximum dry density. Cylindrical specimens were prepared using optimum mix with different proportion of cement (3, 6 and 9 per cent) and cured for period of 7, 14 and 28 days in desiccator. Several tests such as proctor test, unconfined compressive strength test, splitting tensile strength test and soaked CBR test were carried out.

Findings

After analyzing the variation of test results with varying cement content and curing period, maximum compressive strength of 10 MPa and maximum tensile strength of 1.5 MPa was found for specimen having 9 per cent cement content cured for a period of 28 days. It was concluded that copper slag and fly ash when mixed in optimum proportion and stabilized with 6 and 9 per cent cement can be effectively used as granular material in sub base and base layer of road pavement.

Originality/value

A typical flexible pavement section was designed and checked using IITPAVE software which gave desired results. This paper may add value in the areas of pavement design, waste utilization, etc.

Details

World Journal of Engineering, vol. 15 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 24 February 2020

Eric Asa, Monisha Shrestha, Edmund Baffoe-Twum and Bright Awuku

Environmental issues caused by the production of Portland cement have led to it being replaced by waste materials such as fly ash, which is more economical and safer for the…

Abstract

Purpose

Environmental issues caused by the production of Portland cement have led to it being replaced by waste materials such as fly ash, which is more economical and safer for the environment. Also, fly ash is a material with sustainable properties. Therefore, this paper aims to focus on the development of sustainable construction materials using 100% high-calcium fly ash and potassium hydroxide (KOH)-based alkaline solution and study the engineering properties of the resulting fly ash-based geopolymer concrete. Laboratory tests were conducted to determine the mechanical properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In phase I of the study, carbon nanotubes (CNTs) were added to determine their effect on the strength of the geopolymer mortar. The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce similar (comparable) strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates a considerable amount of heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond was unable to form a stronger bond. This study also determined that the addition of CNTs to the mix makes the geopolymer concrete tougher than the traditional concrete without CNT.

Design/methodology/approach

Tests were conducted to determine properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In Phase I of the study, CNTs were studied to determine their effect on the strength of the geopolymer mortar.

Findings

The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce the same strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates too much heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond. This study also determined that the addition of CNTs to the mix makes the concrete tougher than concrete without CNT.

Originality/value

This study was conducted at the construction engineering and management concrete laboratory at North Dakota State University in Fargo, North Dakota. All the experiments were conducted and analyzed by the authors.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 6
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 26 August 2014

Ankita Pritam Praharaj, Dibakar Behera, Tapan Kumar Bastia, Prasanta Rath and Priyabrata Mohanty

– This paper aims to prepare BisGMA (bisphenol-A glycidyldimethacrylate)/jute fibre/fly ash hybrid composites with improved mechanical and corrosive properties.

Abstract

Purpose

This paper aims to prepare BisGMA (bisphenol-A glycidyldimethacrylate)/jute fibre/fly ash hybrid composites with improved mechanical and corrosive properties.

Design/methodology/approach

BisGMA prepolymer was first synthesised using diglycidyl ether of bisphenol-A and methacrylic acid. Then 2-hydroxy ethylacrylate-treated jute fibre and sodium hydroxide-treated fly ash were incorporated in the fabrication of composites using dicumyl peroxide, cobalt naphthenate and N,N-dimethyl aniline as catalyst, accelerator and promoter, respectively. The composition of BisGMA, jute fibre and fly ash was kept constant, whereas treated and untreated jute fibre and fly ash were used alternatively.

Findings

Treatment of both jute and fly ash leads to improved mechanical properties of composites. However, treated fabric plays a dominant role compared to treated fly ash as filler. Among all the composites, the one having both treated jute fibre and treated fly ash is the most suitable composite for structural applications.

Research limitations/implications

The present investigation has come up with a hybrid composite that can be used for a wide range of applications like low-cost housing and structural projects, structural laminates, etc., as it is both corrosion- and moisture-resistant. It is also the most durable from the mechanical point of view. There is also a scope of using other fillers instead of fly ash to study the changes brought about in the mechanical properties.

Originality/value

The above composites have never been fabricated before.

Details

Pigment & Resin Technology, vol. 43 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 December 1998

I.V. Suresh, C. Padmakar, Prabha Padmakaran, M.V.R.L. Murthy, C.B. Raju, R.N. Yadava and K. Venkata Rao

The potential problems and their consequences due to fly ash disposal have been well studied around the world. Ash pond is a common available disposal facility for thermal power…

2158

Abstract

The potential problems and their consequences due to fly ash disposal have been well studied around the world. Ash pond is a common available disposal facility for thermal power plants. The pond ash is subjected to weathering and the ions present in ash migrate to the soil and subsequently to the ground water over a period of time. A study has been carried out at Vijayawada Thermal Power Station (VTPS), Andhra Pradesh, India, to monitor the ground water quality in order to determine the potential impact of ash ponds. It has been found that ground water quality is deteriorated due to the presence of fly ash ions (macro and micro such as Fe, Ca, Mg etc.) which were leached out from the ash up to some extent. The contamination is likely to increase in the case of toxic and other ions with the passage of time. The presence of vegetative cover and plant growth on the down stream slope and fly ash ponds which are covered by soil may effectively control the leaching of ions.

Details

Environmental Management and Health, vol. 9 no. 5
Type: Research Article
ISSN: 0956-6163

Keywords

Article
Publication date: 19 June 2018

Banu Sugözü

The purpose of this study is to investigate the potential of fly ash in automotive brake lining materials.

Abstract

Purpose

The purpose of this study is to investigate the potential of fly ash in automotive brake lining materials.

Design/methodology/approach

Three brake linings containing fly ash (36, 41 and 46 Wt.%) were designed and produced by dry-mixing, pre-forming and hot pressing. The surface hardness of all brake lining samples was measured by using Brinell hardness tester. The density of the specimens was determined based on Archimedean principle in water. The friction and wear characteristics of the brake lining samples were determined using a real brake disc-type tester. Detailed examinations on the worn surface were analyzed using a scanning electron microscopy.

Findings

Fly ash can be good alternative as space filler to reduce the cost for brake lining.

Originality/value

The present study has successfully demonstrated that there is a high potential for commercial applications of brake linings including fly ash as a filler.

Details

Industrial Lubrication and Tribology, vol. 70 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 26 April 2023

S.N. Basavana Gowda, Subhash Yaragal, C. Rajasekaran and Sharan Kumar Goudar

In recent years, fire accidents in engineering structures have often been reported worldwide, leading to a severe risk to life and property safety. The present study is carried…

Abstract

Purpose

In recent years, fire accidents in engineering structures have often been reported worldwide, leading to a severe risk to life and property safety. The present study is carried out to evaluate the performance of Ground Granulated Blast Furnace Slag (GGBS) and fly ash–blended laterized mortars at elevated temperatures.

Design/methodology/approach

This test program includes the replacement of natural river sand with lateritic fine aggregates (lateritic FA) in terms of 0, 50 and 100%. Also, the ordinary Portland cement (OPC) was replaced with fly ash and GGBS in terms of 10, 20, 30% and 20, 40 and 60%, respectively, for producing blended mortars.

Findings

This paper presents results related to the determination of residual compressive strengths of lateritic fine aggregates-based cement mortars with part replacement of cement by fly ash and GGBS exposed to elevated temperatures. The effect of elevated temperatures on the physical and mechanical properties was evaluated with the help of microstructure studies and the quantification of hydration products.

Originality/value

A sustainable cement mortar was produced by replacing natural river sand with lateritic fine aggregates. The thermal strength deterioration features were assessed by exposing the control specimens and lateritic fine aggregates-based cement mortars to elevated temperatures. Changes in the mechanical properties were evaluated through a quantitative microstructure study using scanning electron microscopy (SEM) images. The phase change of hydration products after exposure to elevated temperatures was qualitatively analyzed by greyscale thresholding of SEM images using Image J software.

Details

Journal of Structural Fire Engineering, vol. 14 no. 4
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 11 July 2019

Gopalakrishnan Rajagopalan

The durability of concrete structures, especially built-in corrosive environments, starts to deteriorate after 20–30 years, even though they have been designed for more than 60…

Abstract

Purpose

The durability of concrete structures, especially built-in corrosive environments, starts to deteriorate after 20–30 years, even though they have been designed for more than 60 years of service life. The durability of concrete depends on its resistance against a corrosive environment. Inorganic Polymer concrete, or geopolymer concrete, has been emerging as a new engineering material with the potential to form an alternative to conventional concrete for the construction industry. The purpose of this paper is to conduct the investigation on corrosion of the geopolymer materials prepared using GGBS blended with low calcium fly ash in different percentages and sodium hydroxide, sodium silicate as activators and cured in ambient conditions (25±5°C).

Design/methodology/approach

GGBS was replaced by fly ash at different levels from 0 to 50 percent in a constant concentration of 12M. The main parameters of this study are the evaluation of strength characteristics of geopolymer concrete and resistance against corrosion by conducting accelerated corrosion test (Florida method).

Findings

From the test results it is observed that the strength of the geopolymer concrete with GGBS in ambient curing performs well compared to geopolymer concrete with GGBS blended with fly ash. The GPCE sample (40 percent replacement of fly ash to GGBS) shows better results and the resistance against corrosion was good, compared to all other mixes.

Research limitations/implications

The outcomes of this investigation will be useful for the researchers and the construction industry.

Practical implications

This paper results that optimum percentage of fly ash should be blended with GGBS against the corrosion attack. This investigation indicates that GGBS without the combination of fly ash can be utilized in a normal environment. These findings will definitely be useful for the ready-mix concrete manufacturers and the construction Industry.

Social implications

Disposal of industrial wastes causes pollution to the environment. Industrial wastes are utilized for the production of geopolymer concrete, which is the alternative material for the construction industry.

Originality/value

From the observation of the previous literature, till now there was no investigation on geopolymer concrete for corrosion under ambient curing conditions, as such this investigation could be considered as the new investigation.

Details

Engineering, Construction and Architectural Management, vol. 26 no. 8
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 9 July 2021

K. Arunkumar, Muthukannan Muthiah, Suresh Kumar A., Chithambar Ganesh A. and Kanniga Devi R.

Inefficient waste disposal technique and cement production methodology caused significant environmental impacts, leading to global warming. The purpose of the research was to…

Abstract

Purpose

Inefficient waste disposal technique and cement production methodology caused significant environmental impacts, leading to global warming. The purpose of the research was to invent an effective, sustainable technology to use the wastes and alternate for cement in concrete. Geopolymer technology could be the most desirable solution to use the wastes into an effective product.

Design/methodology/approach

The wood waste ash derived from nearby tea shops was used as an alternate binder for fly ash. The replacement of WWA with FA was varied from 0 to 100% at 10% intervals. In this research, setting and mechanical features of Geopolymer Concrete (GPC) along with Waste wood ash (WWA) was carried out. The influence of wood waste ash in the microstructure of the GPC was also assessed using scanning electron microscope and X-ray diffraction analysis.

Findings

The findings revealed that 30% replacement of wood waste ash was performed higher in all measured features. Besides, the formation of different phases was also observed with the inclusion of wood waste ash.

Research limitations/implications

The demand for fly ash was increased in recent years, and the fly-based GPC has required more alkaline solution and temperature curing. Hence, there was a research gap on finding an alternative binder for fly ash.

Originality/value

The research novelty was to use the wood waste ash, which has inbuilt alkaline compounds on the production of sustainable geopolymer. The finding showed that the wood waste ash could be alternate fly ash that eliminates the environmental impacts and economic thrust.

Details

World Journal of Engineering, vol. 19 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 9 May 2016

Kumaran Coopamootoo and Reshma Rughooputh

The cementitious/chemical properties of the untreated CFA are dependent on the coal composition and previous burning conditions. The purpose of this paper is to investigate…

229

Abstract

Purpose

The cementitious/chemical properties of the untreated CFA are dependent on the coal composition and previous burning conditions. The purpose of this paper is to investigate whether untreated CFA can efficiently reduce cement replacement and does not require further combustion treatment to be a viable cement replacement.

Design/methodology/approach

Two types of mixes: Type I concrete and PCFA (Type I and 30 per cent untreated CFA) concrete were batched and subjected to compressive strength tests and cyclic exposures of 5 per cent sodium sulphate (Na2SO4) and 5 per cent magnesium sulphate (MgSO4), respectively.

Findings

PCFA mix was 41.1 and 35.21 per cent lower in strength compared to Type I at 28 and 56 days correspondingly. Continuous-sulphate-exposure resulted in slow but continued strength development for both mixes. However, the strengths of PCFA cubes exposed to cyclic sulphate and sulphate/magnesium salts continued to increase at a lower rate from their corresponding 28-day strength (rate of 18.7 per cent and strength 27.30 MPa in Na2SO4 and rate of 10.0 per cent and strength 25.30 MPa in MgSO4) while Type I specimens subjected to the same exposure conditions experienced drastic reductions in strength (rate of −15.0 per cent and strength 33.21 MPa in Na2SO4 and rate of −23.4 per cent and strength 29.94 MPa in MgSO4).

Research limitations/implications

Results justify the need for additional tests essentially: at different percentage replacement of untreated CFA, fineness of materials, chloride environment and longer exposures, to address the cementitious properties of untreated CFA as cement replacement.

Originality/value

Treatment methods for fly ashes require undoubtedly additional resources, energy input and cost. This paper paves the way to define whether untreated CFA can be used as cement replacement in concrete.

Details

Structural Survey, vol. 34 no. 2
Type: Research Article
ISSN: 0263-080X

Keywords

Article
Publication date: 22 October 2019

Kanwar Pal Singh, Arvind Kumar and Deo Raj Kaushal

This paper aims to the transportation of high concentration slurry through pipelines that will require thorough understanding of physical and rheological properties of slurry, as…

Abstract

Purpose

This paper aims to the transportation of high concentration slurry through pipelines that will require thorough understanding of physical and rheological properties of slurry, as well as its hydraulic flow behavior. In spite of several contributions by the previous researchers, there is still a need to enrich the current understanding of hydraulic conveying through pipeline at various flow parameters. The pilot plant loop tests, particularly at high concentrations, are tedious, time-consuming and complex in nature. Therefore, in the current research the prediction methodology for slurry pipeline design based on rheological model of the slurry is used for calculation of pressure drop and other design parameters.

Design/methodology/approach

It has been established that slurry rheology plays important role in the prediction of pressure drop for laminar and turbulent flow of commercial slurries through pipeline. In the current research fly ash slurry at high concentration is chosen for rheological analysis. The effect of particle size and solid concentration is experimentally tested over the rheological behavior of slurry and based on the rheological data a correlation is developed for calculation of pressure drop in slurry pipeline.

Findings

The present study strongly supports the analytical approach of pressure drop prediction based on the rheological parameters obtained from the bench scale tests. The rheological properties are strongly influenced by particle size distribution (PSD), shear rate and solid mass concentration of the slurry samples. Pressure drop along the pipeline is highly influenced by flow velocity and solid concentration. The presence of coarser particles in the slurry samples also leads to high pressure drop along the pipeline. As the concentration of solid increase the shear stress and shear viscosity increase cause higher pressure drop.

Research limitations/implications

The transportation of slurry in the pipeline is very complex as there are lot of factors that affect the flow behavior of slurry in pipelines. From the vast study of literature it is found that flow behavior of slurry changes with the change in parameters such as solids concentration, flow velocity, PSD, chemical additives and so on. Therefore, the accurate prediction of hydraulic parameter is very difficult. Different slurry samples behave differently depending upon their physical and rheological characteristics. So it is required to study each slurry samples individually that is time-consuming and costly.

Practical implications

Nowadays in the world, long distance slurry pipelines are used for the transportation of highly concentration slurries. Many researchers have carried out an experiment in the design aspects of hydraulic transportation system. Rheological characteristics of slurry also play crucial role in determining important parameters of hydraulic conveying such as head loss in commercial slurry pipeline. The current research is useful for the prediction of pressure drop based on rheological behavior of fly ash slurry at various solid concentrations. The current research is helpful for finding the effect of solid concentration and flow velocity on the flow behavior of slurry.

Social implications

Slurry pipeline transportation has advantages over rail and road transportation because of low energy consumption, economical, less maintenance and eco-friendly nature. Presently majority of the thermal power plants in India and other parts of the world dispose of coal ash at low concentration (20 per cent by weight) to ash ponds using the slurry pipeline. Transporting solids in slurry pipelines at higher concentrations will require a thorough knowledge of pressure drop. In the current research a rheological model is proposed for prediction of pressure drop in the slurry pipeline, which is useful for optimization of flow parameters.

Originality/value

All the experimental work is done on fly ash slurry samples collect from the Jharli thermal power plant from Haryana State of India. Bench scale tests are performed in the water resource laboratory of IIT Delhi for physical and rheological analysis of slurry. It has been shown in the results that up to solid concentration of 50 per cent by mass all the samples behave as non-Newtonian and follows a Herschel–Bulkley model with shear thickening behavior. In the present research all the result outcomes are unique and original and does not copied from anywhere.

Details

World Journal of Engineering, vol. 16 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

1 – 10 of over 1000