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Article
Publication date: 11 February 2021

Guichen Zhang, Heng Peng, Hongtao Zhang, Juzhen Tang and Yinghua Liu

The safety assessment of engineering structures under repeated variable dynamic loads such as seismic and wind loads can be considered as a dynamic shakedown problem. This…

Abstract

Purpose

The safety assessment of engineering structures under repeated variable dynamic loads such as seismic and wind loads can be considered as a dynamic shakedown problem. This paper aims to extend the stress compensation method (SCM) to perform lower bound dynamic shakedown analysis of engineering structures and a double-closed-loop iterative algorithm is proposed to solve the shakedown load.

Design/methodology/approach

The construction of the dynamic load vertexes is carried out to represent the loading domain of a structure under both dynamic and quasi-static load. The SCM is extended to perform lower bound dynamic shakedown analysis of engineering structures, which constructs the self-equilibrium stress field by a series of direct iteration computations. The self-equilibrium stress field is not only related to the amplitude of the repeated variable load but also related to its frequency. A novel double-closed-loop iterative algorithm is presented to calculate the dynamic shakedown load multiplier. The inner-loop iteration is to construct the self-equilibrated residual stress field based on the certain shakedown load multiplier. The outer-loop iteration is to update the dynamic shakedown load multiplier. With different combinations of dynamic load vertexes, a dynamic shakedown load domain could be obtained.

Findings

Three-dimensional examples are presented to verify the applicability and accuracy of the SCM in dynamic shakedown analysis. The example of cantilever beam under harmonic dynamic load with different frequency shows the validity of the dynamic load vertex construction method. The shakedown domain of the elbow structure varies with the frequency under the dynamic approach. When the frequency is around the resonance frequency of the structure, the area of shakedown domain would be significantly reduced.

Research limitations/implications

In this study, the dynamical response of structure is treated as perfect elastoplastic. The current analysis does not account for effects such as large deformation, stochastic external load and nonlinear vibration conditions which will inevitably be encountered and affect the load capacity.

Originality/value

This study provides a direct method for the dynamical shakedown analysis of engineering structures under repeated variable dynamic load.

Details

Engineering Computations, vol. 38 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 4 February 2021

Guichen Zhang, Hongtao Zhang, Heng Peng and Yinghua Liu

High-rise tower structures supported by side frame structure and viscous damper in chemical industry can produce plasticity under dynamic loads, such as wind and…

Abstract

Purpose

High-rise tower structures supported by side frame structure and viscous damper in chemical industry can produce plasticity under dynamic loads, such as wind and earthquake, which will heavily influence the long-term safety operation. This paper aims to systematically study the optimization design of these structures by free vibration and dynamic shakedown analysis.

Design/methodology/approach

The transfer matrix method and Euler–Bernoulli beam vibration are used to study the free vibration characteristic of the simplified high-rise tower structure. Then the extended stress compensation method is used to construct the self-equilibrated stress by using the dynamic load vertexes and the lower bound dynamic shakedown analysis for the structure with viscous damper. Using the proposed method, comprehensive parametric studies and optimization are performed to examine the shakedown load of high-rise tower with various supported conditions.

Findings

The numerical results show that the supported frame stiffness, attached damper or spring parameters influence the free vibration and shakedown characters of high-rise tower very much. The dynamic shakedown load is lowered down quickly with external load frequency increasing to the fundamental natural frequency of the structure under spring supported condition, while changed little with the damping connection. The optimized location and parameter of support are obtained under dynamical excitations.

Research limitations/implications

In this study, the high-rise tower structure is simplified as a cantilever beam supported by a short cantilever beam and a damper under repeated dynamic load, and linear elasticity for solid is assumed for free vibration analysis. The current analysis does not account for effects such as large deformation, stochastic external load and nonlinear vibration conditions which will inevitably be encountered and affect the load capacity.

Originality/value

This study provides a comprehensive method for the dynamical optimization of high-rise tower structure by combining free vibration and shakedown analysis.

Details

Engineering Computations, vol. 38 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 6 February 2018

Weidong Zhu, Quan Ku, Yong Wu, HongTao Zhang, Yibo Sun and Chao Zhang

With the advancement of social economy, science and technology, nowadays, people face increasingly complex decision-making problems and ever-growing decision-associated…

Abstract

Purpose

With the advancement of social economy, science and technology, nowadays, people face increasingly complex decision-making problems and ever-growing decision-associated information contents. Owing to the unique advantages of the evidence theory, evidence decision flow fits in well with the cognitive process of human beings, which provides us with an effective decision method. However, traditional evidence theories are built upon the one-dimensional evidence recognition framework, which merely reflects the reliability of information determined by evidence source and as such may fail to present the characteristic information of evidence source itself or the information required for the process of determining reliability. This greatly influences processes in decision-making, such as evidence processing and combination. This essay aims to propose a two-dimensional evidence-reasoning theory to address specific decision problems.

Design/methodology/approach

This article uses a two-dimensional evidence framework to reflect the process and characteristic information of evidence source based on the traditional evidence framework. As a result, evidence is processed and combined by two-dimensional modified information.

Findings

This research is of theoretical and practical significance by extending theoretical connotation, fully utilizing precise evidence information and therefore meeting the requirements of efficient and accurate decision-making performances.

Originality/value

The theory adds a two-dimension to modify and capture evidence on the basis of the traditional evidence framework. This proposal has significant theoretical and practical value to expand evidence theory and provides more accurate use of evidence information, higher efficiency and quality requirements and more precise decision-making.

Article
Publication date: 4 November 2014

Hubo Cai, Asadur Rahman, Xing Su and Hongtao Zhang

The purpose of this study is to create a framework that integrates GIS and microscopic simulation to optimize the placement of road barriers in emergency evacuation and…

Abstract

Purpose

The purpose of this study is to create a framework that integrates GIS and microscopic simulation to optimize the placement of road barriers in emergency evacuation and assess the effectiveness via simulation. Human populations are at risk from many hazards including man-made and natural disasters, sudden events that are difficult to predict and prevent, but have catastrophic consequences. A critical issue in disaster management is timely evacuation that considers the dynamic traffic demand and congestions under dynamic hazard conditions. University campuses face a unique challenge in developing effective emergency evacuation plans due to their complex site configurations, high-dense buildings and dynamic spatial-temporal distribution of population.

Design/methodology/approach

The framework was implemented and tested on the main campus of the Western Michigan University to optimize the placement and configuration of road barriers to achieve an effective utilization of road network when the demand way exceeds the capacity. The resulting system was also used to test the effectiveness of the phased evacuation notification strategy, both with and without the optimal road barrier strategy.

Findings

It concluded that the newly created framework and its implementation could assist emergency evacuation planning for university campuses. It also concluded that placing road barriers at appropriate locations could reduce the evacuation time by 20 per cent or more under a variety of evacuation scenarios.

Originality/value

The originality of this research lies in three aspects of: a university campus context, the integration of GIS and microscopic simulation in emergency evacuation and the simulation based turn restriction strategy.

Details

International Journal of Disaster Resilience in the Built Environment, vol. 5 no. 4
Type: Research Article
ISSN: 1759-5908

Keywords

Content available
Article
Publication date: 9 October 2009

Jochen Wirtz, Robert Johnston and Christopher Khoe Sin Seow

554

Abstract

Details

Journal of Service Management, vol. 20 no. 5
Type: Research Article
ISSN: 1757-5818

Article
Publication date: 29 April 2022

Sonal Thukral, Deep Shree and Shakshi Singhal

With the rapid increase in the consumption of electrical and electronic innovations, responsible management and recycling of electronic waste (e-waste) or waste electrical…

Abstract

Purpose

With the rapid increase in the consumption of electrical and electronic innovations, responsible management and recycling of electronic waste (e-waste) or waste electrical and electronic equipment (WEEE) has been a significant concern for the governments, stakeholders, researchers and industry practitioners around the world. Consumer awareness, disposal behaviour and perception are chief facets of designing sustainable management strategies. Although researchers have widely studied e-waste over many years, the research focusing on consumer awareness about e-waste recycling has gained momentum recently. This paper aims to systematise the existing literature and explore future research prospects on household e-waste sorting behaviour.

Design/methodology/approach

Web of science (WoS) core collection was searched using selected keywords to identify relevant articles published from 2001 to 2021. The search resulted in 1,156 research articles published from 2001 to 2021. After a detailed study, 85 articles were shortlisted for in-depth review. The review was conducted based on global trends, top journals, most prolific authors, most active e-waste research countries, and institutions centring on consumer participation in e-waste disposal and recycling behaviour. The present research has also identified around eleven factors that seem to have a bearing on consumer behaviour towards storage, disposal and recycling of e-waste.

Findings

E-waste research has gained increased attention in the last five years. The majority of the studies has focused on motivational factors and ignore the risks associated with handling e-waste. The present study reports the pertinent issue of lack of awareness among the masses about e-waste handling and disposal. Thus, bringing to the fore the lack of awareness programmes and initiatives. The analysis presents the gaps in the literature and future research agendas.

Originality/value

The review article will help in providing an in-depth understanding of consumer behaviour towards storage, disposal and recycling of e-waste and delineates the future direction of research that may be undertaken in this field of study.

Details

Benchmarking: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1463-5771

Keywords

Article
Publication date: 21 April 2022

Junwei Zheng, Yu Gu, Zhenduo Zhang, Hongtao Xie, Peikai Li and Hongyang Li

While existing literature emphasizes the importance of empowerment in construction projects, the working mechanisms of empowering leadership in the project context are…

Abstract

Purpose

While existing literature emphasizes the importance of empowerment in construction projects, the working mechanisms of empowering leadership in the project context are unclear. Based on conservation of resources (COR) theory, this study aimed to examine the relationship between empowering leadership and project performance, highlighting the mediation roles of creative self-efficacy and leadermember exchange and the moderation role of perceived overqualification.

Design/methodology/approach

The authors collected data from 287 project members in different projects and tested the integrated conceptual model through moderated mediation analysis with bootstrapping strategy.

Findings

The results revealed that empowering leadership was positively related to project performance through creative self-efficacy and leader–member exchange. Perceived overqualification served as significant moderator.

Originality/value

The findings contribute to the understanding of empowering leadership in projects by verifying and extending the resource acquisition and investment process in the project context. The results of this study also demonstrated that creative belief and social exchange facilitate the effectiveness of project members' task efforts and outcomes and that perceived overqualification might not exert a detrimental effect on project performance.

Details

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

Keywords

Article
Publication date: 29 April 2022

Junwei Zheng, Yu Gu, Lan Luo, Yunhua Zhang, Hongtao Xie and Kai Chang

Project complexity is a critical issue that has increasingly attracted attention in both academic and practical circles. However, there are still many gaps in the research…

Abstract

Purpose

Project complexity is a critical issue that has increasingly attracted attention in both academic and practical circles. However, there are still many gaps in the research on project complexity, such as the differentiated conceptualization of complexity and disjointed operationalization in the measurements. Therefore, this paper aims to conduct a systematic and detailed literature review on the concept, dimensions, assessment, and underlying mechanisms of project complexity.

Design/methodology/approach

A systematic literature review methodology was applied to search and synthesize the research on project complexity, and a final sample of 74 journal articles was identified.

Findings

This study first summarizes the concepts of project complexity from three different theoretical perspectives, and then identifies different approaches of measurement, evaluation, or simulation to assess project complexity. This paper finally establishes an integrative framework to synthesize the antecedents, mediators and moderators, and outcomes of project complexity, generating four suggestions for future research.

Originality/value

This study summarizes the definition and operationalization of project complexity to reduce the discrepancies in the existing research and offers an integrative framework to offer a broad overview of the current understanding of project complexity, providing a potential way forward for addressing project complexity.

Details

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

Keywords

Article
Publication date: 2 July 2020

Hongtao Shen, Artie W. Ng, John Zhang and Liyan Wang

This paper aims to reflect on the special issue that has collected studies by the research community in China pertinent to the country’s recent developments in…

Abstract

Purpose

This paper aims to reflect on the special issue that has collected studies by the research community in China pertinent to the country’s recent developments in sustainability accounting, management and policy, as well as to suggest possible future avenues of studies.

Design/methodology/approach

This paper articulates the current status of researching sustainability accounting, management and policy in China that is instigated by the country’s regulatory initiatives under its political economy. It highlights the papers accepted for the special issue, their areas of focus and the underlying characteristics.

Findings

It points out that the accepted research papers concentrate on issues related to corporate social responsibility disclosures, sustainability reporting and environmental management in China from the perspectives of the domestic stakeholders.

Research limitations/implications

Future studies are likely to be increasingly interdisciplinary in nature and requires academia, policymakers and practitioners to make better collaborative efforts in researching about China’s sustainability and the efficacy of their engagement with stakeholders.

Practical implications

Studies on alignment between China’s further developments and UN’s sustainable development goals (SDGs) are particularly considered desirable as the country continues its globalization initiatives. Education about sustainability accounting for the working professionals and their next generation is much needed for China in support of developing a more sustainable economy aligned with UN's SDGs.

Social implications

Scholars in China actively developing their research interests in this field reflect critical thinking about the country’s pursuit of sustainable development within a social-political economy that is dissimilar to the West. In the meantime, the country continues to develop into a significant stakeholder of the world’s sustainability implying expectation of transparency in sustainability performance.

Originality/value

With reference to the review exercise conducted for the special issue, it suggests that there are surging interests in researching accountability for sustainability across the local and international communities to facilitate much needed knowledge exchange. The country and indigenous culture of China, as well as its institutions in relation to sustainability, would require much further exploration in our world under globalization.

Details

Sustainability Accounting, Management and Policy Journal, vol. 11 no. 5
Type: Research Article
ISSN: 2040-8021

Keywords

Article
Publication date: 10 June 2021

Ru Zhang, Chuanzhen Huang, Jun Wang, Hongtao Zhu and Hanlian Liu

The purpose of this study is to fabricate high-aspect-ratio grooves with high surface quality by femtosecond laser (FS) to improve the machinability of silicon carbide…

Abstract

Purpose

The purpose of this study is to fabricate high-aspect-ratio grooves with high surface quality by femtosecond laser (FS) to improve the machinability of silicon carbide (SiC) and optimize the process parameters in micromechanical applications.

Design/methodology/approach

Four contrast experiments are reported to characterize the FS laser grooving process for SiC with polarization direction, crystal orientation, multi-pass scanning and z layer feed, respectively. The effects of different experimental conditions on the groove characteristics, material removal rate (MRR), aspect ratio, heat affected zone (HAZ) and surface roughness Ra are analyzed.

Findings

The influence of increasing laser fluence and multi-scanning pass on the groove depth is greater than on the groove width. The MRR, aspect ratio, HAZ and Ra increased with the increase of laser fluence and multi-scanning pass. The direction of laser polarization affects the direction of hot electron injection but has little effect on the material characteristics. FS laser ablation is an isotropic process and there is no obvious change in different crystal orientations. The z-layer feed can significantly increase the groove width and depth and reduce HAZ and Ra. The maximum aspect ratio of 82.67% was fabricated.

Originality/value

The results contribute to the understanding of the removal mechanism and reduce the friction of the microfluidic device and improve the flowability in the FS laser ablation of SiC. This paper provides suggestions for the selection of suitable process parameters and provides a wider possibility for the application of micro-texture on SiC.

Details

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

Keywords

1 – 10 of 39