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Article
Publication date: 27 December 2011

Weijian Huang, Pei Niu and Wei Du

Parallel processing technology was applied to accelerate the calculation speed of the water quality forecasting model. The parallel algorithm proposed was based on the…

Abstract

Parallel processing technology was applied to accelerate the calculation speed of the water quality forecasting model. The parallel algorithm proposed was based on the message-passing interface (MPI). It mainly aims at enhancing the computation speed of the water quality forecasting model of Jiaozhou Bay, and decomposes the material transport issue into many sub-duties. The model was run in a MPI message cluster system. The result indicates that, by using this method, the computation efficiency for solving material transportation module is increased by approximately more than 60%.

Details

World Journal of Engineering, vol. 8 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 26 June 2019

Wang Lijun and Li Qingbo

Asphalt mixture is widely used in road engineering, and its performance research is particularly important. But the study of asphalt mixture performance needs a lot of tests, such…

Abstract

Purpose

Asphalt mixture is widely used in road engineering, and its performance research is particularly important. But the study of asphalt mixture performance needs a lot of tests, such as bending test, splitting test and so on. It also needs a lot of time and material resources. The purpose of this paper is to obtain test results through finite element numerical simulation, and show that this saves a lot of manpower and material resources.

Design/methodology/approach

The mechanical parameters of the material are obtained through uniaxial compression tests. The true stress and plastic strain are calculated according to nominal stress and nominal strain. A constitutive model is established. Then a finite element model of asphalt mixture is established. The numerical simulation and performance study of asphalt mixture bending test is carried out. At the same time, according to the above method, the asphalt mixture is subjected to freeze-thaw cycles and ultraviolet aging, and the mechanical parameters are obtained by a uniaxial compression test. A numerical model is established to simulate the bending characteristics of asphalt mixture after freeze-thaw cycles and ultraviolet aging.

Findings

A uniaxial compression test of the asphalt mixture is conducted to obtain nominal stress and nominal strain. The true stress and plastic strain are calculated and the elastic modulus is established with Poisson’s ratio as the elastic part, and the true stress and plastic strain as the plastic part. The model is constructed, the finite element model is established and the bending test is numerically simulated. The verified trend is consistent, and the method is feasible. According to the above method, the concrete is subjected to freeze-thaw cycle and ultraviolet aging, and the finite element model is established by using uniaxial compression test to obtain parameters. The bending test is simulated and the verification method is feasible. With the increase of the number of freeze-thaw cycles and the increase of UV aging time, the maximum bending strain of SBS modified asphalt mixture and matrix asphalt mixture is decreased .The low-temperature performance of SBS modified asphalt mixture is better than that of matrix asphalt mixture.

Originality/value

A method of simulating asphalt mixture test by finite element method numerical simulation is established. By using this method, the performance of asphalt mixture is studied, which saves a lot of manpower and material resources. At the same time, this method can be used to study the characteristics of asphalt mixture under complex conditions.

Details

International Journal of Structural Integrity, vol. 10 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 29 January 2020

Le Yun, Jingyuan Wan, Ge Wang, Ju Bai and Bing Zhang

The purpose of this paper is to analyze the relationship between the demographic characteristics of top management teams (TMTs) (i.e. age, gender, administrative level, senior…

1039

Abstract

Purpose

The purpose of this paper is to analyze the relationship between the demographic characteristics of top management teams (TMTs) (i.e. age, gender, administrative level, senior management experience and educational background) and megaproject performance, with respect to schedule, cost, quality, safety and technological innovation. The results shed new light on the effectiveness of different types of TMT.

Design/methodology/approach

This paper collected secondary and objective data from 208 TMT members in 42 megaprojects and employed hierarchical regression analysis to test the research hypotheses.

Findings

The findings revealed that age has a significant influence on schedule performance; gender has a significant influence on safety performance; senior management experience has a significant influence on cost performance; and educational background has a significant influence on both schedule and technological innovation performance. However, this study did not find evidence of a significant relationship between the administrative level and megaproject performance.

Research limitations/implications

This paper mainly focused on China’s megaprojects, most of which are globally influential (e.g. Hong Kong–Zhuhai–Macao Bridge and Shanghai Expo), however this sampling approach still limits the generalizability of research findings to other contexts.

Originality/value

The results of this paper contribute to a better understanding of how management team capabilities translate into better project achievements. This paper also provides implications on the criteria for selecting top megaproject managers to optimize the composition of the TMT and realize better performance.

Details

Engineering, Construction and Architectural Management, vol. 27 no. 5
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 14 November 2023

Masah Alomari and Ibrahim Aladi

Financial inclusion is considered one of the strategic tools for sustainable development and one of the types of corporate social responsibility disclosures. This study aims to…

Abstract

Purpose

Financial inclusion is considered one of the strategic tools for sustainable development and one of the types of corporate social responsibility disclosures. This study aims to focus on the association between the disclosure of financial inclusion activities and Syrian banking companies’ performance.

Design/methodology/approach

Different regression models were suggested to examine the hypotheses leading to a better understanding of the relationship between financial inclusion and Syrian banking performance for the period 2005 to 2020 using the STATA 17.

Findings

The results showed a positive association between financial inclusion disclosure and Syrian bank performance, with low participation in financial inclusion activities (8%).

Research limitations/implications

The study recommends that the Central Bank of Syria work on developing an index of financial inclusion for the Syrian environment, with the issuance of legislation and laws that obligate all listed banks to disclose their financial inclusion activities as a part of their social responsibility.

Originality/value

This study incorporates the relationship between the disclosure of financial inclusion activities and the performance of Syrian banking companies, which has been neglected by most studies on financial inclusion. Therefore, this study sheds light on this positive relationship, which could have important repercussions in reviving the deteriorating Syrian economy following the crisis it went through, which, in turn, led to Syria’s high inflation affecting the poor and vulnerable disproportionately.

Details

Journal of Financial Economic Policy, vol. 16 no. 1
Type: Research Article
ISSN: 1757-6385

Keywords

Article
Publication date: 9 May 2023

Kuleni Fekadu Yadeta, Sudath C. Siriwardane and Tesfaye Alemu Mohammed

Reliable estimations of the extent of corrosion and time required to reach specific safety limits are crucial for assessing the reliability of aging reinforced concrete (RC…

Abstract

Purpose

Reliable estimations of the extent of corrosion and time required to reach specific safety limits are crucial for assessing the reliability of aging reinforced concrete (RC) bridges. Engineers and decision-makers can use these figures to plan suitable inspection and maintenance operations.

Design/methodology/approach

Analytical, empirical and numerical approaches for estimating the service life of corroded RC structures were presented and compared. The concrete cover cracking times, which were predicted by the previously proposed analytical models, were compared with the experimentally obtained cracking times to identify the model/s for RC bridges. The shortcomings and limitations of the existing models are discussed.

Findings

The empirical models typically depend on the rate of corrosion, diameter of steel reinforcement and concrete cover depth and based on basic mathematical formula. In contrast, the analytical and numerical models contain the strength and stiffness properties of concrete as well as type of corrosion products and incorporate more complex mechanical factors. Four existing analytical models were analyzed and their performance was evaluated against existing experimental data in literature. All the considered analytical models were assumed thick-walled cylinder models. The maximum difference between observed cracking time from different test data and calculated cracking time using the developed models is 36.5%. The cracking times extend with increase in concrete cover and decrease with corrosion current density. The development of service life prediction models that considers factors such as heterogeneity of concrete, non-uniform corrosion along rebar, rust production rate and a more accurate representation of the corrosion accommodating region are some of the areas for further research.

Research limitations/implications

Outcome of this paper partially bridge the gap between theory and practice, as it is the basis to estimate the serviceability of corrosion-affected RC structures and to propose maintenance and repair strategies for the structures. For structural design and evaluation, the crack-width criterion is the greatest practical importance, and structural engineers, operators and asset managers should pay close attention to it. Additionally, repair costs for corrosion-induced serviceability failures, particularly concrete cracking and spalling, are significantly higher than those for strength failures. Therefore, to optimize the maintenance cost of RC structures, it is essential to precisely forecast the serviceability of corrosion-affected concrete structures. The lifespan of RC structures may be extended by timely repairs. This helps stake holders to manage the resources.

Practical implications

In order to improve modeling of corrosion-induced cracking, important areas for future research were identified. Heterogeneity properties of concrete, concept of porous zone (accommodation effect of pores should be quantified), actual corrosion morphology (non-uniform corrosion along the length of rebar), interaction between sustain load and corrosions were not considered in existing models. Therefore, this work suggested for further researches should consider them as input and develop models which have best prediction capacity.

Social implications

This work has positive impact on society and will not affect the quality of life. Predicting service life of structures is necessary for maintenance and repair strategy plans. Optimizing maintenance strategy is used to extend asset life, reduce asset failures, minimize repair cost, and improve health and safety for society.

Originality/value

The degree of accuracy and applicability of the existing service life prediction models used for RC were assessed by comparing the predicted cracking times with the experimentally obtained times reported in the literature. The shortcomings of the models were identified and areas where further research is required are recommended.

Details

International Journal of Structural Integrity, vol. 14 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

Open Access
Article
Publication date: 16 August 2019

Zheng Zhao and Yali Wen

The purpose of this paper is to measure the influence factors of their preferences for urban forest, marginal values of various properties and relative values of different scheme…

Abstract

Purpose

The purpose of this paper is to measure the influence factors of their preferences for urban forest, marginal values of various properties and relative values of different scheme portfolios, thus arriving indirectly at the city residents’ demand for urban forest improvement.

Design/methodology/approach

This paper, based on the data from the 2015–2017 field survey questionnaire of city residents over the radius of Beijing’s 5th Ring Road, uses the choice experiment method (CEM) to conduct a study of its residents’ demand for urban forest.

Findings

Beijing’s city residents are generally inclined to accept a relatively low payment of urban forest while hoping to access a relatively high urban afforestation coverage with the construction of relatively many city parks, especially focusing on the specialized park management; the marginal values of biodiversity and greenery coverage are far higher than those of greenbelts in quantity and the maximum marginal value of biodiversity remains as high as RMB29.42, indicating that the city residents do not favor much the number of greenbelts over other aspects but they generally hope to achieve a higher greenery coverage and a richer biodiversity.

Research limitations/implications

Generally speaking, what Beijing City needs most is not continuing the increase in the number of greenbelts, but engaging in the rational retrofit of its existing greenbelts and optimizing its urban forest structure.

Originality/value

This paper may provide reference for determining the city residents’ payment criteria for urban forest and will be of equally great significance to developing cities and their urban forest.

Details

Forestry Economics Review, vol. 1 no. 1
Type: Research Article
ISSN: 2631-3030

Keywords

Article
Publication date: 31 May 2019

Wang Jiawei and Sun Quansheng

Swivel construction is a new bridge construction method, which can minimize the impact on railway and highway traffic. Previous studies were based on single factor and static…

Abstract

Purpose

Swivel construction is a new bridge construction method, which can minimize the impact on railway and highway traffic. Previous studies were based on single factor and static analysis, which cannot reflect the real state of structures. The purpose of this paper is to establish a dynamic model of the structure and to analyze the situation under multi-variable coupling effects to accurately simulate the real state of the structure.

Design/methodology/approach

Finite element software ANSYS was used to establish dynamic model of turntable structure and then to analyze the effects of multiple factors on total stress, friction stress and slipping distance of the turntable structure.

Findings

It is concluded that the unbalanced weight and radius of spherical hinges have great influence on the turntable structure, so the design should be strictly considered. Friction stress and angular acceleration have little effect on the turntable structure.

Originality/value

This paper provides simulation of the whole process of swivel construction method. Whereas previous studies focused on static analysis, this paper focuses on the dynamic analysis of swivel construction method. The mechanics of the swivel structure under multiple factors was analyzed. According to the analysis results, the design parameters of the turntable structure are optimized.

Details

International Journal of Structural Integrity, vol. 10 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

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