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Article
Publication date: 29 November 2021

Guangyuan Wu, Haitao Zhang, Junfeng Sun and Tengjiang Yu

In order to evaluate the rheological properties of asphalt more comprehensively and effectively, and to explore and discuss the practicability of relevant models in the…

Abstract

Purpose

In order to evaluate the rheological properties of asphalt more comprehensively and effectively, and to explore and discuss the practicability of relevant models in the evaluation of the rheological properties of asphalt.

Design/methodology/approach

Based on the rheological and viscoelastic theories, temperature scanning, frequency scanning and multiple stress creep recovery (MSCR) tests of different modified asphalt were carried out by dynamic shear rheometer (DSR) to obtain relevant viscoelastic parameters and evaluate the high temperature properties of different modified asphalt. Based on the time-temperature equivalence principle, the main curve was constructed to study the viscoelastic properties of asphalt in a wider frequency domain. The main curve was fitted with the CAM model, and the rheological properties of different modified asphalt were evaluated through the analysis of model parameters. The creep stiffness and creep velocity of different modified asphalt were obtained through the rheological test of bending beam (BBR), and the low-temperature performance of different modified asphalt was analyzed by using Burgers model to fit the creep compliance.

Findings

The results show that the high temperature rheological properties of several modified asphalt studied in the test are ranked from best to worst as follows: PE modified asphalt > SBS modified asphalt > SBR modified asphalt. Short-term aging can improve the high temperature performance of asphalt, and different types of modifiers can promote or inhibit this improvement effect. Based on BBR test and Burgers model fitting analysis, SBR modified asphalt has the best low temperature performance, followed by SBS modified asphalt, while PE modified asphalt has poor low temperature performance, so it is not suitable to be used as road material in low temperature area.

Originality/value

Combined with effective evaluation methods, the rheological properties of asphalt at different temperatures and angles were systematically evaluated, and the evolution of rheological properties of asphalt characterized by model parameters was further analyzed by advanced model simulation.

Details

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

Keywords

Article
Publication date: 2 December 2020

Wenting Wang, Lirong Jian, Qiuyun Guo, Haitao Zhang and Wenxing Liu

The purpose of this study is to build a link between narcissistic supervision and employees' change-oriented organizational citizenship behaviors (OCBs). On the basis of…

Abstract

Purpose

The purpose of this study is to build a link between narcissistic supervision and employees' change-oriented organizational citizenship behaviors (OCBs). On the basis of the social dynamics of state paranoia theory, the study examines the relationship between narcissistic supervision and employees' change-oriented OCBs, and explores how this relationship is mediated by psychological safety and affective organizational commitment.

Design/methodology/approach

Using data collected from a sample of 183 employee–leader dyads from a technology company in China, the study examines the mediating effects of psychological safety and affective organizational commitment on the relationship between narcissistic supervision and employees' change-oriented OCBs. Structural equation modeling is used to analyze the data.

Findings

The results indicate that narcissistic supervision has a negative effect on psychological safety and affective organizational commitment; psychological safety mediates the relationship between narcissistic supervision and affective organizational commitment; and affective organizational commitment mediates the relationship between psychological safety and employees' change-oriented OCBs. The results also show that the negative effect of narcissistic supervision on employees' change-oriented OCBs is mediated by psychological safety and subsequently affective organizational commitment.

Originality/value

This study contributes to the literature by linking narcissistic supervision and employees' change-oriented OCBs and suggesting that psychological safety and affective organizational commitment are two critical mediators of this relationship. This study not only advances research on the “dark side” of narcissistic supervision, but also sheds light on the underlying mechanism of narcissistic supervision and employees' change-oriented OCBs from the psychological and emotional perspectives.

Article
Publication date: 7 November 2016

Xing Han, Haitao Zhang, Bo Shao, Dongtao Wang, Longgang Cheng, Yadong Guo, Ke Qin and Jianzhong Cui

The purpose of this paper is to investigate the influence of sprue distributions on the flow field and temperature field of the cladding casting process and verify the…

Abstract

Purpose

The purpose of this paper is to investigate the influence of sprue distributions on the flow field and temperature field of the cladding casting process and verify the simulation results by experiments.

Design/methodology/approach

A steady-state mathematic model for the coupling of fluid flow, heat transfer and solidification to describe the process of cladding casting was present. The effect of sprue distributions on melt flow and temperature field was discussed. Based on the numerical simulation results, the cladding billet was prepared successfully. Moreover, the model has been verified against by temperature measurements during the cladding casting process.

Findings

There is a good agreement between the measured and calculated results. The homogeneity of melt flow determines the formability of cladding billets and circular temperature difference affects the bonding of the two alloys. The AA4045/AA3003 cladding billet with no defects in size of f140/f110 mm was fabricated successfully. The alloy elements diffused across the interface and formed diffusion layer with a thickness of 15 µm. The interface bonding strength is higher than the tensile strength of AA3003, indicating the metallurgical bonding between two alloys.

Research limitations/implications

The casting parameters are limited to the aluminum alloy cladding billet in size of f140/f110 mm in this paper.

Originality/value

There are few reports of cladding billet, which are used to prepare condense pipes of automotive engines. The effect of distribution schemes on the cladding casting process is rarely studied.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 26 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 2 August 2021

Tengjiang Yu, Haitao Zhang, Junfeng Sun, Yabo Wang, Shuang Huang and Dan Chen

Using typical structure of asphalt pavement in Harbin area of China, and the formula of generalized friction coefficient between base and surface layers of asphalt…

Abstract

Purpose

Using typical structure of asphalt pavement in Harbin area of China, and the formula of generalized friction coefficient between base and surface layers of asphalt pavement in cold area is established.

Design/methodology/approach

Through structural characteristics analysis of asphalt pavement in cold area, the generalized formula of friction coefficient between base and surface layers of asphalt pavement in cold area is derived. The formula can quickly calculate the friction coefficient between layers of asphalt pavement.

Findings

Based on quantitative analysis to the contacting state between layers of asphalt pavement in cold area, the relationships between generalized friction coefficient and resilient modulus of asphalt mixtures, temperature shrinkage coefficient and temperature have been established.

Originality/value

The findings can enrich the description methods about the contacting state between layers of asphalt pavement, and have a certain theoretical and practical value. Through the application of the formula of generalized friction coefficient between layers, it can provide a technical basis for the asphalt pavement design, construction and maintenance in cold area.

Details

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

Keywords

Article
Publication date: 18 October 2021

Haitao Zhang, Junfeng Sun and Mingyang Gong

The purpose of this study is to compare and analyze the anti-aging durability of asphalt and asphalt mixture under the conditions of inherent and improved performance. The…

Abstract

Purpose

The purpose of this study is to compare and analyze the anti-aging durability of asphalt and asphalt mixture under the conditions of inherent and improved performance. The research contents include: the mechanical properties (dynamic stability, bending strain, freeze-thaw splitting tensile strength ratio (TSR)) of different modified asphalt mixtures were tested by using the best modified asphalt.

Design/methodology/approach

The anti-aging durability of different modified asphalt was analyzed by using the results of macro tests such as penetration and softening point as evaluation indexes. Meanwhile, the change of the asphalt colloid instability index (Ic) in the aging process was used as the evaluation index to verify the results of the macroscopic test, and the best modified asphalt was obtained. On this basis, the composition of different modified asphalt mixtures was designed by using the best modified asphalt. Meanwhile, water stability was used as evaluation indexes to study the anti-aging durability of different modified asphalt mixtures.

Findings

The results show that styrene-butadiene-styrene (SBS) modified asphalt has better aging resistance. Due to the special storage time, the performance of rubber asphalt is also the best. Meanwhile, in terms of modified asphalt mixture, its high temperature performance and durability of anti-aging is as follows: 4% SBS /16% rubber modified asphalt mixture (IV) > 4% SBS modified asphalt mixture (II) > asphalt mixture (90#) (I) > 16% rubber modified asphalt mixture (III). The low temperature performance and durability of anti-aging is as follows: Ⅱ > IV > Ⅰ > Ⅲ. The water stability performance and durability of anti-aging is as follows: IV > Ⅲ > Ⅱ > Ⅰ.

Originality/value

The research results have important theoretical and guiding significance for exploring the change of intrinsic properties and improved properties of asphalt and asphalt mixture in the aging process and revealing the anti-aging mechanism of different modified asphalt mixtures.

Details

Multidiscipline Modeling in Materials and Structures, vol. 18 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 18 May 2021

Ning Wang, Haitao Zhang and Huizhong Xiong

In order to unravel the evolution of microstructure characteristics and the change of mechanical properties of bituminous mixture in the freezing and thawing environment…

Abstract

Purpose

In order to unravel the evolution of microstructure characteristics and the change of mechanical properties of bituminous mixture in the freezing and thawing environment in cold region, this study starts from macroscopic experiments and analyzes the changes in mechanical properties of asphalt mixtures before and after freezing and thawing in detail. On this basis, the displacement of key particles in the structure of asphalt mixture under the action of external forces (before and after freezing and thawing) is simulated through the combination macroscopic and microscopic methods.

Design/methodology/approach

The climate in China exhibits high complexity and diversity, divided into five zones based on the temperature difference from south to north. Considering that the significant effect of geography and natural climate on the design, construction and maintenance of asphalt pavement, the criterion for the road construction at different areas should be highly different.

Findings

The results show that the mechanical properties of asphalt mixture greatly decrease due to the influence of freeze-thaw, and the displacement of key particles in the structure of asphalt mixture (several representative particle sizes were selected through experiments) is obviously observed because of the action of external force. By analyzing the variation of several key particle sizes after freezing-thawing cycle, the gradation standard of asphalt mixture aggregate suitable for cold area was obtained. The research results have certain theoretical and practical value for the design and application of asphalt mixture in cold area.

Originality/value

The results show that the mechanical properties of asphalt mixture greatly decrease due to the influence of freeze-thaw, and the displacement of key particles in the structure of asphalt mixture (several representative particle sizes were selected through experiments) is obviously observed because of the action of external force. By analyzing the variation of several key particle sizes after freezing-thawing cycle, the gradation standard of asphalt mixture aggregate suitable for cold area was obtained. The research results have certain theoretical and practical value for the design and application of asphalt mixture in cold area.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 14 April 2022

Guangyuan Wu, Haitao Zhang, Qixin Ge, Junfeng Sun and Tengjiang Yu

In order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium…

Abstract

Purpose

In order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium temperature state can be deeply explored.

Design/methodology/approach

In this paper, the needle penetration test and temperature scanning test were designed for 90# and 70# bitumen as test materials, and the boundary of medium temperature zone of 90# and 70# bitumen was accurately determined by data analysis method. A mathematical model was established based on principal component analysis, and a comprehensive evaluation index was proposed to evaluate the evolution of temperature viscoelastic characteristics of road asphalt by means of standardization and rotational dimensionality reduction.

Findings

The test results show that the medium temperature zone of 90# asphalt is [−5 ± 1°C, 38 ± 1°C], and the medium temperature zone of 70# asphalt is [0 ± 1°C, 51 ± 1°C]. According to the viscoelastic response of road asphalt in the medium temperature zone, the medium temperature zone can be divided into three evolution stages: weak viscoelastic stage, viscoelastic equilibrium stage, strong viscoelastic weak stage. Analysis based on the intrinsic viscosity fillip target describing the various intrinsic viscoelastic index represents the viscoelastic properties of bitumen from different angles, and limitations inherent stick fillip for target put forward the integrated the inherent stick fillip mark information, as well as targeted and accurate evaluation of road asphalt temperature comprehensive evaluation indexes in the evolution of the viscoelastic properties of IM-T. Finally, the temperature data of asphalt pavement in several representative regions of China are compared with the determined medium temperature region, and it is proved that the research on the evolution of viscoelastic characteristics of asphalt pavement under the medium temperature condition has important practical significance.

Originality/value

The boundary of medium temperature zone of 90# and 70# base asphalt was determined, and the viscoelastic characteristic evolution of road asphalt under medium temperature state was studied deeply. Aiming at the limitation of intrinsic viscoelastic index, a comprehensive evaluation index IM-T which not only integrates the information of intrinsic viscoelastic index but also can accurately evaluate the evolution of temperature viscoelastic characteristics in road asphalt is proposed.

Details

Multidiscipline Modeling in Materials and Structures, vol. 18 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 10 September 2021

Junfeng Sun, Haitao Zhang, Guangyuan Wu, Zuoqiang Liu, Yuping Feng and Minghao Jia

In order to give full play to the function of noise reduction of asphalt pavement, it is necessary to understand its internal sound absorption mechanism. Therefore, the…

Abstract

Purpose

In order to give full play to the function of noise reduction of asphalt pavement, it is necessary to understand its internal sound absorption mechanism. Therefore, the purpose of this study is to establish a micro model of the pore structure of asphalt mixture with the help of finite element method (FEM), discuss the noise reduction mechanism of asphalt pavement from the micro perspective and analyze and evaluate the noise attenuation law of the pore structure.

Design/methodology/approach

The FEM was used to establish the microscopic model of the pore structure of asphalt mixture. Based on the principle of acoustics, the noise reduction characteristics of asphalt pavement were simulated. The influence of gradation and pore characteristics on the noise reduction performance of asphalt pavement was analyzed.

Findings

The results show that the open graded friction course-13 (OGFC-13) has excellent performance in noise reduction. The resonant sound absorption structure composed of its large porosity can effectively reduce the pavement noise. For asphalt concrete-13 (AC-13) and stone matrix asphalt-13 (SMA-13), the less resonant sound absorption structure makes them have poor sound absorption effect. In addition, the variation rules of noise transmission loss (TL) curve and sound absorption coefficient curve of three graded asphalt mixtures were obtained. At the same time, the peak noise reduction values of OGFC-13, AC-13 and SMA-13 were obtained, which were 650Hz, 1000Hz and 800Hz, respectively.

Originality/value

The results show that the simulation results can well reflect and express the experimental results. This will provide a reference for further exploring the sound absorption mechanism and its variation rule of porous asphalt pavement. It also has some positive significance for the application of low noise asphalt pavement.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 6
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 August 2016

Kesheng Zuo, Haitao Zhang, Ke Qin and Jianzhong Cui

The purpose of this paper is to study the effect of feeding scheme on melt flow and temperature field during the steady-state of level-pour direct-chill (DC) casting of…

Abstract

Purpose

The purpose of this paper is to study the effect of feeding scheme on melt flow and temperature field during the steady-state of level-pour direct-chill (DC) casting of A390 alloy hollow billet and optimize the design of feeding scheme.

Design/methodology/approach

Melt flow and temperature field are investigated by numerical simulation, which is based on a three-dimensional mathematical model and well verified by experiments.

Findings

The numerical results reveal that both melt flow and temperature field are obviously affected by the feeding scheme. The homogeneity of melt flow and temperature field in hollow billet with the feeding scheme of modified four inlets are better than the other feeding schemes. Experimental results show that crack can be eliminated by increasing the number of feeding inlets. The primary Si size appears unaffected while the distribution of primary Si particles is highly affected by the change of feeding scheme. Only with the feeding scheme of modified four inlets can fine and uniformly distributed primary Si particles be achieved.

Practical implications

The paper includes implications for the design of feeding scheme in level-pour DC casting of hollow billet for practical use.

Originality/value

This paper develops different feeding schemes for level-pour DC casting of hollow billet and optimizes the design of feeding scheme.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 26 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 4 April 2016

Xiaojun Xu, Wu He, Ping Yin, Xiaobo Xu, Yuting Wang and Haitao Zhang

The purpose of this paper is to present a new tool, business network information ecological chain (BNIEC) aiming to solve the current information problems in business…

1176

Abstract

Purpose

The purpose of this paper is to present a new tool, business network information ecological chain (BNIEC) aiming to solve the current information problems in business network, make more profits to business websites and to maintain the sustainable development of the business network environment in Internet of Things (IoT) era.

Design/methodology/approach

From multi-disciplinary perspectives, learning from the knowledge in information ecology, economics, the IoT and system theory, this paper first analyzes the positioning of BNIEC in different subjects. Second, it proposes the definition, components and characteristics of BNIEC and designs the BNIEC concept map helping to understand the BNIEC system. Last, this paper builds the structural model and the information flow models of BNIEC.

Findings

The study first presents the concept of BNIEC and based on the trans-disciplinary point of view, builds the structure model of BNIEC from three aspects: nodes, relations among nodes and link modes and illustrates the model using the knowledge from the system theory. Also, it builds two kinds of the information flow models by the related information knowledge in IoT.

Originality/value

This paper aims to introduce not only a new tool but an ecological idea to business network companies, to create a pleasant network environment, more than that, to make more benefits for themselves. Meanwhile, it has important significance in the sustainable development of the business network environment, business websites, business network information resources and information technology. Especially in today’s IoT era, it shows an ecological thinking to solve the information problems in business network that we may face in the future.

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