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Article
Publication date: 1 July 2021

Arun M., Muthukumaran M. and Balasubramanian S.

Dissimilar materials found applications in the structural fields to withstand the different types of loads and provide multi-facet properties to the final structure…

Abstract

Purpose

Dissimilar materials found applications in the structural fields to withstand the different types of loads and provide multi-facet properties to the final structure. Aluminum alloy materials are mostly used in aerospace and marine industries to provide better strength and safeguard the material from severe environmental conditions. The purpose of this study is to develop new material with superior strength to challenge the severe environmental conditions.

Design/methodology/approach

In the present investigation, friction stir welding (FSW) dissimilar joints were prepared from AA6061 and AA5083 aluminum alloys, and the weld nugget (WN) was reinforced with hard reinforcement particles such as La2O3 and CeO2. The tribological and mechanical properties of the prepared materials were tested to analyze the suitability of material in the aerospace and marine environmental conditions.

Findings

The results showed that the AA6061–AA5083/La2O3 material exhibited better mechanical and tribological characteristics. The FSW dissimilar AA6061–AA5083/La2O3 material exhibited lower wear rate of 7.37 × 10−3 mm3/m and minimum friction coefficient of 0.31 compared to all other materials owing to the reinforcing effect of La2O3 particles and the fine grains formed by FSW process at WN region. Further, FSW dissimilar AA6061–AA5083/La2O3 material displayed a maximum tensile strength and hardness of 378 MPa and 118 HV, respectively, among all the other materials tested.

Originality/value

This work is original and novel in the field of materials science engineering focusing on tribological characteristics of friction stir welded dissimilar aluminum alloys by the reinforcing effect of hard particles such as La2O3 and CeO2.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 14 October 2021

Sheetal Gounder, Abid Hasan, Asheem Shrestha and Abbas Elmualim

Although the adverse effects of construction activities on the environment and the need for sustainable construction practices are recognised in both research and…

Abstract

Purpose

Although the adverse effects of construction activities on the environment and the need for sustainable construction practices are recognised in both research and practice, any significant shift in the selection and use of construction materials from the sustainability perspective has not taken place in many building projects. Still, conventional construction materials are widely used in building projects in both developed and developing countries. This study attempts to identify the main barriers to the use of sustainable materials in building projects in an advanced economy such as Australia.

Design/methodology/approach

This study adopted a questionnaire survey approach to examine the main reasons behind the low usage of sustainable materials in building projects. Based on the relative importance index, exploratory factor analysis and multinomial logistic regression analysis, the study examined the main barrier measures and barrier factors to the use of sustainable materials in building projects.

Findings

The findings reveal that critical barriers to the use of sustainable materials are related to cost and profit considerations, the unwillingness of the key stakeholders to incorporate these materials into building projects, lack of incentives and government policies. The factor analysis reduced the critical barrier measures into three factors: techno-economic considerations, cost and delay concerns and resistance to use. Furthermore, multinomial regression analysis based on the extracted factors identified techno-economic considerations as the main barrier factor to the use of sustainable materials in building projects.

Practical implications

The empirical results of this research can inform construction practitioners, organisations and policymakers on how to increase the use of sustainable building materials in the construction industry.

Originality/value

Identification of barriers to the use of sustainable building materials is a prerequisite to improve their uptake and use in the construction industry. The study fills a gap in the existing research on the use of sustainable materials in building projects in Australia.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

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Article
Publication date: 19 October 2021

Cagla Keles and Fatih Yazicioglu

The purpose of this paper is to identify the sustainability conditions of primary schools in Turkey within the scope of the life cycle assessment (LCA). It is aimed to…

Abstract

Purpose

The purpose of this paper is to identify the sustainability conditions of primary schools in Turkey within the scope of the life cycle assessment (LCA). It is aimed to develop optimum alternatives to reduce the environmental impact of primary schools and reach environmental sustainability targets of the sustainable development goals in Turkey.

Design/methodology/approach

From the construction project of 103 buildings located in Istanbul, 10 case buildings with various typical plans were chosen for analysis. The results regarding their life cycle energy and carbon emission for material production, operation and maintenance stages were calculated for a lifespan of 50 years. Results were evaluated and compared within the scope of environmental sustainability. Optimum alternatives for improving the environmental sustainability and performances of selected case buildings’ facades were developed, and the life cycle energy and carbon emission for proposed conditions were calculated. The obtained results were evaluated for current and proposed conditions.

Findings

Results showed that reinforced concrete material contributes the most to the life cycle-embodied energy and CO2 emission of buildings. Cooling load increases the life cycle operational energy (LCOE) and CO2 emission of buildings. Using high-performance glazing significantly reduces LCOE and CO2 emission. Recycled and fiber-based materials have significant potential for reducing life cycle-embodied energy and CO2 emission.

Originality/value

This study has been developed in response to achieving sustainable development targets on public buildings in Turkey. In this regard, external walls of primary schools were analyzed within the scope of LCA and recommendations were made to contribute to the policies and regulations requested by the Government of Turkey. This study proves that alternative and novel materials have great potential for achieving sustainable public buildings. The study answers to questions about reducing the environmental impact of primary school buildings by using LCA approach with a holistic point of view.

Details

Smart and Sustainable Built Environment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2046-6099

Keywords

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Article
Publication date: 15 October 2021

Ferhat Ceritbinmez and Ahmet Yapici

The purpose of this study is to obtain strong materials with multiwall carbon nanotubes (MWCNTs) doped and investigate laser cut of MWCNTs also find the effect of the…

Abstract

Purpose

The purpose of this study is to obtain strong materials with multiwall carbon nanotubes (MWCNTs) doped and investigate laser cut of MWCNTs also find the effect of the laser cutting parameters on composite materials.

Design/methodology/approach

The laminated composite plates were manufactured by using a vacuum infusion process. The mechanical properties of the composite materials produced were determined according to American Society for Testing and Materials (ASTM) D3039M, ASTM D3171, ASTM D 792 and ASTM D2583. A 130 Watts carbondioxide (CO2) laser cutting machine was used for drilling the two different composite plates with a thickness of 1.6–1.5 mm. Three variables were considered as process parameters including laser power (in three levels of 84.50, 104.00 and 127.40 W), cutting speed (in three levels of 4, 6, 8 mm/s) and 14 mm fixed focal position.

Findings

The fibers could not be cut due to insufficient melting in the experiments performed using 84.50 and 104.00 W laser power but the cutting was successfully completed when the laser power was 127.40 W. However, as the cutting speed increased, the contact time of the laser beam with the material decreased, so the kerf decreased, but the increased laser power created a thermal effect, causing an increase in hardness around the cutting surface. This increase was lower in MWCNTs doped composites compared to pure composites. It has been found that the addition of nanoparticles to layered glass fiber composite materials played an effective role in the strength of the material and affected the CO2 laser cutting quality.

Originality/value

This study is a unique study in which the CO2 laser cutting method of MWCNT-doped composite materials was investigated and the machinability without cutting errors, such as delamination, splitting, distortion and burring using the most suitable laser cutting parameters was revealed.

Details

Aircraft Engineering and Aerospace Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 25 October 2021

Chunwei Li, Quansheng Sun and Yancheng Liu

As the service time of bridges increases, the degradation of bending capacity, the lack of safety reserves and the decrease in bridge reliability are common in early built…

Abstract

Purpose

As the service time of bridges increases, the degradation of bending capacity, the lack of safety reserves and the decrease in bridge reliability are common in early built bridges. Due to the defective lateral hinge joints, hollow slab bridges are prone to cracking of hinge joint between plates, transverse connection failure and stress of single plates under the action of long-term overload and repeated load. These phenomena seriously affect the bending capacity of the hollow slab bridge. This paper aims to describe a new method of simply supported hollow slab bridge reinforcement called polyurethane–cement (PUC) composite flexural reinforcement.

Design/methodology/approach

This paper first studies the preparation and tensile and compressive properties of PUC composite materials. Then, relying on the actual bridge strengthening project, the 5 × 20 m prestressed concrete simply supported hollow slab was reinforced with PUC composites with a thickness of 3 cm within 18 m of the beam bottom. Finally, the load test was used to compare the performance of the bridge before and after the strengthening.

Findings

Results showed that PUC has high compressive and tensile strengths of 72 and 46 MPa. The static test revealed that the measured values and verification coefficients of the measured points were reduced compared with those before strengthening, the deflection and strain were reduced by more than 15%, the measured section stiffness was improved by approximately 20%. After the strengthening, the lateral connection of the bridge, the strength and rigidity of the structure and the structural integrity and safety reserves were all significantly improved. The application of PUC to the flexural strengthening of the bridge structure has a significant effect.

Originality/value

As a new type of material, PUC composite is light, remarkable and has good performance. When used in the bending strengthening of bridge structures, this material can improve the strength, rigidity, safety reserve and bending capacity of bridges, thus demonstrating its good engineering application prospect.

Details

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

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Article
Publication date: 13 October 2021

Laura Blackburne, Koorosh Gharehbaghi and Amin Hosseinian-Far

The aims and objectives of this research are to establish whether or not the transition into green building in high-rise construction is practical. This is after…

Abstract

Purpose

The aims and objectives of this research are to establish whether or not the transition into green building in high-rise construction is practical. This is after considering several perspectives including financial, economic, environmental, and social. This subsequently leads to an evaluation on whether or not the continuation with a standard conventional build of high-rise buildings remains to be the most feasible option. Such objectives, therefore, aim to allow for validation of how and why high-rise construction designs are impacted through green buildings effects.

Design/methodology/approach

Through six defined steps, the methodology commences with an introductory section of what it means to build green. This section is further broken down to evaluate what factors are involved in constructing a green building. Furthermore, the life cycle energy (LCE) is used as a framework to evaluate the knock-on effects of green buildings and subsequent high-rise construction design implications.

Findings

Through defining the ongoing relationship of green materials and sustainable design, various implications for high-rise constructions were discovered. First and foremost, it was determined that the LCE is the central consideration for any high-rise building design. In evaluating the LCE, and overall operating energy of the 50-year cycle of a building was carried out. As the results showed, the operating energy represents around 85% of the total energy that is consumed at the end of the 50 years cycle of the building. Precise LCE calculation can lead to a more efficient design for high-rise buildings. As a result, an increased understanding of the current status of green buildings within the construction industry is paramount. This understanding leads to a better insight into the contributing factors to green building in high-rise construction and the construction industry in general.

Originality/value

The potential contribution that can be gained from this research is the awareness that is raised in the research and development of green buildings in high-rise construction. This can be achieved by using certain materials such as new energy-efficient building materials, recycled materials and so on. This research will contribute to defining a new way of sustainable buildings, particularly for high-rise construction. The outcome of the research will be beneficial for practitioners such as design engineers and other related professions.

Details

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

Keywords

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Article
Publication date: 19 May 2021

Batuhan Özakın, Bilal Çolak and Naci Kurgan

The last stage of the cold rolling process is skin-pass rolling and one of its most significant goals is to obtain appropriate topography on the surface of the sheet steel…

Abstract

Purpose

The last stage of the cold rolling process is skin-pass rolling and one of its most significant goals is to obtain appropriate topography on the surface of the sheet steel used extensively such as in automotive industry. The purpose of this paper is to investigate the effect of thickness change and various reduction ratios on roughness transfer of DC04 grade sheet material.

Design/methodology/approach

DC04 grade sheet materials with different reduction ratios and several thicknesses were subjected to skin-pass rolling process in the rolling equipment with a two-high roll. Some roughness parameters were determined as a result of roughness measurements from the surfaces of roughened sheet materials.

Findings

While the roughness transfer is higher in 1-mm thick material in reduction ratios up to 430 micrometers; in reduction ratios above 430 micrometers, it is higher for 1.5-mm thick materials. As the reduction ratio increases in DC04 grade sheet materials, the homogeneity of the roughness distribution in 1-mm thickness sheet material deteriorates, while the roughness distribution in 1.5-mm thickness sheet material is more homogeneous.

Originality/value

This paper demonstrates how material thickness and reduction ratio affect the roughness transfer in skin-pass rolling. The results obtained can be used by optimizing in manufacturing processes.

Details

Industrial Lubrication and Tribology, vol. 73 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 15 September 2021

Xiangyu Du, Junying Yang, Fei Gao, Xiaoming Han and Linlin Su

This paper aims to reveal the effects of the copper third body on different copper matrix friction materials with a novel experimental way called “exogenous powder.”

Abstract

Purpose

This paper aims to reveal the effects of the copper third body on different copper matrix friction materials with a novel experimental way called “exogenous powder.”

Design/methodology/approach

An accurate adding device of exogenous copper powder was designed to control the flow rate. The tribological properties with and without exogenous copper powder were investigated by a pin-on-disc tribometer during dry sliding.

Findings

Experimental results indicate that the Cu addition tends to increase the friction coefficient. For pure Cu material, the exogenous copper third body exhibits poor fluidity on the friction surface, causing serious adhesive wear on the friction interface. For the Cu 90% + 10% Gr material, the plasticity of exogenous copper powder may intensify the deformation of the third body of the surface, presenting layered accumulation distribution. For the pure Cu and Cu 95% + 5% SiO2 material, the Cu addition makes the composition and density of the third body uneven in the direction of depth.

Originality/value

The role of the copper component on different materials is revealed from a new perspective, and the relationship between the third body structure and the friction properties is explored.

Details

Industrial Lubrication and Tribology, vol. 73 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Content available
Article
Publication date: 28 September 2021

Alex Copping, Noorullah Kuchai, Laura Hattam, Natalia Paszkiewicz, Dima Albadra, Paul Shepherd, Esra Sahin Burat and David Coley

Understanding the supply network of construction materials used to construct shelters in refugee camps, or during the reconstruction of communities, is important as it can…

Abstract

Purpose

Understanding the supply network of construction materials used to construct shelters in refugee camps, or during the reconstruction of communities, is important as it can reveal the intricate links between different stakeholders and the volumes and speeds of material flows to the end-user. Using social network analysis (SNA) enables another dimension to be analysed – the role of commonalities. This is likely to be particularly important when attempting to replace vernacular materials with higher-performing alternatives or when encouraging the use of non-vernacular methods. This paper aims to analyse the supply networks of four different disaster-relief situations.

Design/methodology/approach

Data were collected from interviews with 272 displaced (or formally displaced) families in Afghanistan, Bangladesh, Nepal and Turkey, often in difficult conditions.

Findings

The results show that the form of the supply networks was highly influenced by the nature/cause of the initial displacement, the geographical location, the local availability of materials and the degree of support/advice given by aid agencies and or governments. In addition, it was found that SNA could be used to indicate which strategies might work in a particular context and which might not, thereby potentially speeding up the delivery of novel solutions.

Research limitations/implications

This study represents the first attempt in theorising and empirically investigating supply networks using SNA in a post-disaster reconstruction context. It is suggested that future studies might map the up-stream supply chain to include manufacturers and higher-order, out of country, suppliers. This would provide a complete picture of the origins of all materials and components in the supply network.

Originality/value

This is original research, and it aims to produce new knowledge.

Details

Journal of Humanitarian Logistics and Supply Chain Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2042-6747

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Article
Publication date: 27 September 2021

Michele Ciotti, Giampaolo Campana and Mattia Mele

This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature…

Abstract

Purpose

This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim is to provide an updated map of trends and gaps in this relevant research field. Several technologies and investigation methods are examined, thus giving an overview and analysis of the growing body of research.

Design/methodology/approach

Permutations of keywords, which concern materials, technologies and the accuracy of thermoplastic polymeric parts fabricated by AM, are used for a systematic search in peer-review databases. The selected articles are screened and ranked to identify those that are more relevant. A bibliometric analysis is performed based on investigated materials and applied technologies of published papers. Finally, each paper is categorised and discussed by considering the implemented research methods.

Findings

The interest in the accuracy of additively manufactured thermoplastics is increasing. The principal sources of inaccuracies are those shrinkages occurring during part solidification. The analysis of the research methods shows a predominance of empirical approaches. Due to the experimental context, those achievements have consequently limited applicability. Analytical and numerical models, which generally require huge computational costs when applied to complex products, are also numerous and are investigated in detail. Several articles deal with artificial intelligence tools and are gaining more and more attention.

Originality/value

The cross-technology survey on the accuracy issue highlights the common critical aspects of thermoplastics transformed by AM. An updated map of the recent research literature is achieved. The analysis shows the advantages and limitations of different research methods in this field, providing an overview of research trends and gaps.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

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