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Article
Publication date: 22 June 2017

Hussein Adam Abdalla Gibreil and Cheng Pei Feng

In high-temperature regions (tropical regions) temperatures rises in summer, which affects the performance of asphalt pavement. Therefore, we must consider the conditions of…

Abstract

Purpose

In high-temperature regions (tropical regions) temperatures rises in summer, which affects the performance of asphalt pavement. Therefore, we must consider the conditions of asphalt pavement, especially in these regions. This study aims to investigate the influence of high temperature on the stability performance of high-density polyethylene (HDPE) and crumb rubber powder (CRP) modified hot mix asphalt (HMA) using Marshall design parameters and rutting test.

Design/methodology/approach

In this study, three HMA mixtures with 4 per cent HDPE and 15 per cent CRP, 5 per cent HDPE and 10 per cent CRP, and 6 per cent HDPE and 5 per cent CRP concentrations were used for the Marshall stability test and dynamic stability (rutting test) at 60-75°C, and water stability test at 60°C.

Findings

The results showed that when test temperature was increased from 60°C to 75°C, the Marshall stability and dynamic stability of three HDPE- and CRP-modified HMA mixtures decreased, and these three HDPE- and CRP-modified HMA mixtures have a good moisture damage resistance. Of the three HMA mixtures with different HDPE and CRP concentrations, HMA mixtures with 5 per cent HDPE and 10 per cent CRP concentration exhibit optimal Marshall stability, dynamic stability and water stability.

Originality/value

This study showed the effects of high-temperatures changes on the stability performance of HDPE- and CRP-modified HMA mixtures.

Details

Journal of Structural Fire Engineering, vol. 9 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 12 August 2019

Abdelrahman Moukhtar Naser, Hamada Abd El - Wahab, Mohamed Abd El Fattah Moustafa El Nady, Abdelzaher E.A. Mostafa, Long Lin and Ahmed Galal Sakr

This paper aims to investigate the best methods of utilisation of reclaimed asphalt pavements (RAP) in Egypt, to determine the effect of using 100% RAP instead of using virgin…

203

Abstract

Purpose

This paper aims to investigate the best methods of utilisation of reclaimed asphalt pavements (RAP) in Egypt, to determine the effect of using 100% RAP instead of using virgin aggregates and asphalt; investigate the effect of thermoplastic elastomer polymer as asphalt modifier; and also improve the mechanical and physical characteristics and consequently improving the quality of asphalt paving, increasing service life of asphalt-paving and reducing costs.

Design/methodology/approach

Nano acrylate terpolymers were prepared with different % (Wt.) of and were characterised by Fourier transforms infrared (FTIR), for molecular weight (Mw), by thermo gravimetric analysis (TGA) and by transmission electron microscopy (TEM). A 4% (Wt.) of the prepared nanoemulsion terpolymer was mixed with virgin asphalt as a polymer modifier, to improve and reuse of the RAP. The modified binder was tested. The tests conducted include penetration, kinematic viscosity, softening point and specific gravity. Application of Marshall mix design types; hot mix asphalt (HMA), warm mix asphalt (WMA) and cold in place recycled (CIR). Four different mix designs used; control mix contained virgin asphalt by HMA, and the other three mix designs were polymermodified asphalt sample by HMA, WMA and CIR.

Findings

The research results showed that using 4 Wt.% of the prepared nanoemulsion terpolymer to produce hot mix asphalt (HMA) and warm mix asphalt (WMA) achieved higher stability compared to the control mix and cold in place recycled (CIR).

Research limitations/implications

This paper discusses the preparation and the characterisation of nanoemulsion and its application in RAPs to enhance and improve the RAP quality.

Practical implications

Nano-acrylate terpolymer can be used as a new polymer to modify asphalt to achieve the required specifications for RAP.

Originality/value

According to the most recent surveys, Europe produced 265 tonnes of asphalt for road applications in 2014, while the amount of available RAP was more than 50 tonnes. The use of RAP in new blended mixes reduces the need of neat asphalt, making RAP recycling economically attractive.

Article
Publication date: 19 December 2018

Hui Zhang, Yanling Guo, Kaiyi Jiang, David Bourell, Jian Li and Yueqiang Yu

A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study…

Abstract

Purpose

A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters.

Design/methodology/approach

The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density.

Findings

Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength.

Originality/value

This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.

Details

Rapid Prototyping Journal, vol. 25 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 4 October 2011

Colin Jones, Craig Watkins and David Watkins

The purpose of this paper is to address both the measurement of affordability and variations in affordability between local housing market areas (HMAs).

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Abstract

Purpose

The purpose of this paper is to address both the measurement of affordability and variations in affordability between local housing market areas (HMAs).

Design/methodology/approach

The practical data issues that arise from measuring local affordability are reviewed by reference to studies in the UK. The paper argues that local measures should relate to a functional geography of HMAs rather than simply local authority boundaries. This approach is shown to be more theoretically sound but faces data constraints. An empirical case study of the North West of England then follows as a demonstration based on a tiered geography of HMAs. It addresses the constraints on local income data by measuring affordability by reference to a particular household type and associated income.

Findings

Local UK affordability indicators are shown to be primarily about access to home ownership rather than a wider view of local house price structures on affordability. The paper also draws out the importance of affordability measures linked to functional market areas. The results of the analysis presented highlight that there are local differences in house price structures and hence associated differential affordability of house types between local HMAs.

Originality/value

This is the first study that examines affordability at the local level based on functional areas rather than local authority administrative boundaries. This approach gives a truer picture of the variability in local affordability. The applied analysis tackles the data constraints of functional areas and has the potential to be adapted and extended.

Details

International Journal of Housing Markets and Analysis, vol. 4 no. 4
Type: Research Article
ISSN: 1753-8270

Keywords

Article
Publication date: 1 January 1996

Peter G. Frankling

Looks at how hot melt adhesives (HMAs) can be used in product assembly and the white goods market in particular, e.g. washing‐machines, freezers, fridges, etc. because of the need…

Abstract

Looks at how hot melt adhesives (HMAs) can be used in product assembly and the white goods market in particular, e.g. washing‐machines, freezers, fridges, etc. because of the need for permanent or temporary bonds, gap seals and hole plugging. Concludes that HMAs are likely to be used more and more in related fields.

Details

Pigment & Resin Technology, vol. 25 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Abstract

Details

Land Use and Transport
Type: Book
ISBN: 978-0-08-044891-6

Article
Publication date: 2 March 2015

Sultan Jumayev, Aleksandar Borisavljevic, Konstantin Boynov, Juha Pyrhönen and Elena A. Lomonova

The purpose of this paper is to give a simple, fast and universal inductance calculation approach of slotless-winding machines and comparison of inductances of toroidal…

Abstract

Purpose

The purpose of this paper is to give a simple, fast and universal inductance calculation approach of slotless-winding machines and comparison of inductances of toroidal, concentrated and helical-winding machines, since these winding types are widely used among low-power PM machines.

Design/methodology/approach

Harmonic modeling approach is applied to model the magnetic field of the windings in order to calculate the synchronous inductances. The method is based on distinction between electromagnetic properties of different regions in the machine where each region is represented by its own governing equation describing the magnetic field. The governing equations are obtained from Maxwell’s equations by introducing vector potential in order to simplify the calculations.

Findings

Results of the inductances of toroidal, concentrated and helical-winding slotless PM machines, which have the same torque and dimensions, obtained by the proposed analytical method are in good agreement with 3D FEM, where the relative difference is smaller than 15 percent. However, the calculation time of the analytical method is significantly less than in 3D FEM: seconds vs hours. Additionally, from the results it is concluded that the toroidal-winding machine has the highest inductance and DC resistance values among considered machines. Helical-winding machine has lowest inductance and DC resistance values. Inductance of concentrated-winding machine is between inductance of helical and toroidal windings; however, DC resistance of the concentrated windings is comparable with resistance toroidal windings.

Originality/value

In this paper the inductance calculation based on harmonic modeling approach is extended for toroidal and helical-winding machines which makes the method applicable for most of the slotless machine types.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 3 October 2016

Antti Tapio Kurvinen and Jaakko Vihola

Even as multi-story apartment building development proposals in existing neighbourhoods represent a substantial component of policy debate at local planning boards, there is…

1173

Abstract

Purpose

Even as multi-story apartment building development proposals in existing neighbourhoods represent a substantial component of policy debate at local planning boards, there is limited evidence for the impact of such residential developments on surrounding apartment values. This paper aims to address the void in knowledge, and the impact of multi-story apartment building developments on apartment values in residential high-rise areas located outside city and district centres is investigated in Helsinki Metropolitan Area, Finland.

Design/methodology/approach

Whether a multi-story apartment building development is followed by an increase in housing values depends on both positive and negative externalities. To specify valuation effects of proximate development projects, advanced research design combining matched sample methodology and hedonic-based difference-in-difference approach is used.

Findings

It appears from the analysis that completion of a single multi-story apartment building has an immediate positive impact on apartment values within 300 metre radius, while there is no statistically significant impact on price trend.

Research limitations/implications

This paper studies apartment values only in Helsinki Metropolitan Area, Finland, and it is important to notice that local regulations and market conditions may have a notable impact on the outcomes.

Originality/value

This study is the first of its kind to provide with statistically significant evidence for positive impacts from multi-story apartment building development in Finnish residential high-rise areas and may have a crucial role in helping to dispel prejudices related to such developments.

Details

International Journal of Housing Markets and Analysis, vol. 9 no. 4
Type: Research Article
ISSN: 1753-8270

Keywords

Article
Publication date: 17 August 2015

Peggie Rothe, Chris Heywood, Matti Christersson and Anna-Liisa Sarasoja

The purpose of this paper is to increase the understanding of the management of office relocations in Finnish organisations with a focus on the use of, and need for, external…

Abstract

Purpose

The purpose of this paper is to increase the understanding of the management of office relocations in Finnish organisations with a focus on the use of, and need for, external advisory services.

Design/methodology/approach

The study used a sequential mixed method approach. First, the use of relocation-related services, and organisations’ perception of the need for them, was assessed through a questionnaire sent to all organisations with more than 50 employees in the Helsinki Metropolitan Area (HMA). The data includes 83 responses. Subsequently, service experiences, perceived service needs, and the challenges that organisations face in relocation are studied through thematic interviews with 15 organisations that have recently relocated.

Findings

The findings show that, despite facing many challenges when relocating, many organisations do not consider using external service providers. Most organisations do not acknowledge the complexity of the process until afterwards, and they also lack knowledge of the availability of relocation-related services.

Research limitations/implications

The main limitation is the population size of the questionnaire. A larger population would have allowed for more generalisations, but the results do provide insight into the organisations’ issues in managing their relocations.

Practical implications

In order to facilitate the better organisational relocation experiences, and to develop the market for relocation-related services, service providers need to begin educating organisations of the challenges and opportunities of relocation, and successively increase the awareness of the availability of services.

Originality/value

Relocation, when it is considered in the literature, is most often construed as being about location, or site selection. This study approaches the phenomenon from the organisations’ perspective and considers relocation a process that needs to be managed.

Details

Property Management, vol. 33 no. 4
Type: Research Article
ISSN: 0263-7472

Keywords

Article
Publication date: 12 April 2022

Mamdouh Mohamed and Dai Q. Tran

The use of digital inspection or e-inspection of transportation projects has been proven as an efficient method over the last decade. A wide range of studies were dedicated to…

Abstract

Purpose

The use of digital inspection or e-inspection of transportation projects has been proven as an efficient method over the last decade. A wide range of studies were dedicated to developing and applying e-inspection techniques and technologies. However, there is a lack of a comprehensive systematic review and content analysis of using e-inspection in highway construction and maintenance projects. The main objectives of this study were to explore the current trend and identify relevant inspection technologies and their applications for highway construction projects.

Design/methodology/approach

A systematic review of 172 articles from 16 high-ranked academic journals in construction engineering and management published during 2000–2021 was conducted. This process resulted in 67 relevant articles included in the detailed content analysis. The analysis involved synthesizing six main construction elements and work types, nine typical inspection activities, and 23 technologies.

Findings

The result of the analysis showed that among the six construction elements and work types, bridge and hot mix asphalt (HMA) recorded the largest share of e-inspection research. For the nine inspection activities, progress monitoring of construction operations was the highest focused area of e-inspection research. The most common e-inspection technologies are geospatial tools, 3D modeling, and unmanned aircraft systems (UASs). Camera-based inspection has existed for decades, however, has limited research development. The critical success factors in implementing e-inspection in highway projects are sharing data among different technologies, inspector training, and reducing the cost of technology purchase.

Originality/value

This study is one of the first attempts to conduct a content analysis of the e-inspection implementation for highway projects. The findings of this study expose knowledge gaps in contemporary research related to implementation barriers such as cost of purchase and operation of e-inspection technologies and transferring data between technologies.

Details

Engineering, Construction and Architectural Management, vol. 30 no. 7
Type: Research Article
ISSN: 0969-9988

Keywords

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