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The purpose of this paper is to develop an efficient non-iterative model combining advanced numerical methods for solving buoyancy-driven flow problems.

The solution strategy is based on two independent numerical procedures. The Navier-Stokes equation is solved using the non-conforming Crouzeix-Raviart (CR) finite element method with an upstream approach for the non-linear convective term. The advection-diffusion heat equation is solved using a combination of Discontinuous Galerkin (DG) and Multi-Point Flux Approximation (MPFA) methods. To reduce the computational time due to the coupling, the authors use a non-iterative time stepping scheme where the time step length is controlled by the temporal truncation error.

Advanced numerical methods have been successfully combined to solve buoyancy-driven flow problems on unstructured triangular meshes. The accuracy of the results has been verified using three test problems: first, a synthetic problem for which the authors developed a semi-analytical solution; second, natural convection of air in a square cavity with different Rayleigh numbers (103-108); and third, a transient natural convection problem of low Prandtl fluid with horizontal temperature gradient in a rectangular cavity.

The proposed model is the first to combine advanced numerical methods (CR, DG, MPFA) for buoyancy-driven flow problems. It is also the first to use a non-iterative time stepping scheme based on local truncation error control for such coupled problems. The developed semi analytical solution based on Fourier series is also novel.

Construction project stakeholders can have a major effect on delivering projects on time. However, little attempt has been made to address the influence of internal stakeholders on delaying project delivery. This research aims to propose the internal stakeholders' influence as a solution to improving project delivery performance (PDP) in order to boost the value of investment in the construction industry's projects.

In Yemen, a structured questionnaire was distributed to owners, consultants and contractors, 283 of which were found usable after the data screening. A purposeful sampling technique was used and structural equation modelling (SEM) was adopted for analysis. The structural model was drawn up, based on seven categories of influencing factors: labour, supplier, designer, contractor, consultant, sub-contractor and owner.

The results of the structural model suggest that of these seven categories, designers, owners, suppliers and subcontractors have a significant p-value and impact on PDP, while the labour and consultant's impact was not substantiated. The findings support the proposal that internal stakeholders' influence contributes directly to construction PDP.

The influence of stakeholders on PDP is important. Nonetheless, few studies have focussed on their effectiveness, especially in developing countries. This paper's contribution is evaluating the cause–effect relationship between stakeholders' influence and construction PDP through analysis of moment structures (AMOS) analysis. The policy implications of the research are to encourage governments in general and construction companies in particular to take responsibility for improving PDP, as slow execution of construction projects leads to increased costs, failure and abandoning projects.

Delays occur mostly in the construction process of many projects, which can have a consequent effect on the overall performance of the project in areas such as profitability, efficiency and safety. This study aims to suggest a structure that can be applied to manage construction projects effectively and, thus, to reduce delays. The integrated balanced scorecard (BSC) and quality function deployment (QFD) framework proposed in the present study enabled the identification and ranking of the objectives of the financial perspective and the enablers of construction delay mitigation. This will help construction industry professionals prioritize the enabling factors that influence the financial perspective, thereby helping them focus on the achievement of the most important ones which subsequently results in efficiency. Consequently, more tasks are accomplished with the use of less time and resources as the actions tend to be more narrowly focused on the achievement of the most important factors such as client and contractor-related factors, as opposed to the low-value adding factors.

A literature review was conducted to determine the essential factors that would help resolve or reduce delays. A total of 41 mitigation factors (seven financial objectives and 36 enabler objectives) were identified and categorized into four BSC perspectives: financial, client, contractor and project management team, and innovation and learning. Two management tools, the BSC and QFD, were used to develop the system based on the mitigation factors defined.

The results of this study show that the most significant factors affecting the achievement of the financial objectives of the project are mainly customer-related factors, accompanied by factors related to contractors and project management teams. With the fishbone diagram and cause and effect analysis, the proposed BSC and QFD system provides a long-term approach for all stakeholders to help professionals in the construction industry prioritize and reduce delays more effectively. Moreover, the findings of the present study highlight the utility of the integrated BSC and QFD framework in quantifying the strengths of association of different objectives of the financial perspective and the enablers of construction delay mitigation.

The contribution of this paper to the body of knowledge is the proposed integrated structure for BSC and QFD that can serve as a comprehensive and structural approach to rating the essential enabling delay mitigation factors based on the magnitude of their effects on the financial performance of the project. The proposed framework can be considered a novel tool since this is the first integrated BSC and QFD framework for construction delay mitigation. Finally, the proposed BSC and QFD framework, along with the fishbone diagram and cause and effect analysis, provides a long-term strategy for all stakeholders to mitigate delays. Thus, the proposed integrated BSC and QFD framework can serve as a systematic and structural approach for measuring the strength of influence of the enablers of delay mitigation against the financial perspective.

Infrastructure projects are pivotal for regional economic development, but also face low project effectiveness. Leadership is always regarded as a key enabler for project team effectiveness, including vertical leadership and team-level leadership. The purpose of this paper is to examine how vertical leadership facilitates shared leadership in infrastructure project teams.

This paper develops the conceptual model based on the literature review. Then the questionnaire survey was conducted. The empirical data obtained from 117 infrastructure project teams in China were analyzed by partial least squares structural equation modeling (PLS-SEM) for validating the proposed model. Finally, the results were comparatively discussed to explain the dual-pathway between vertical leadership and shared leadership. And the practical implications were presented for the project managers in infrastructure project teams.

Drawing on social learning theory and social cognitive theory, the results show that both participative leadership and task-oriented leadership can facilitate shared leadership. Further, team atmosphere fully mediates the link between participative leadership and shared leadership. Team efficacy fully mediates the relation between task-oriented leadership and shared leadership. Also, role clarity has a negative moderating effect on the former path.

The study extends the knowledge of leadership theory in the construction field. Based on the proposed conceptual model and PLS-SEM results, this study unveils the black box between vertical leadership and shared leadership and contributes to the theory of leadership on how the impact of different vertical leadership on team process promotes shared leadership.

The purpose of this paper is to examine the relationship between top management support, project mission (PM), synergy and project management effectiveness (PME) in the Malaysian local councils. It also attempts to analyze the relative importance and performance of the predictor constructs on the target construct for managerial actions.

Primary data based on 169 respondents were collected and analyzed using PLS-SEM to assess validity, reliability, hypothesis testing and importance-performance matrix analysis (IPMA) of the study constructs.

PM and synergy were found to be significantly and positively associated with PME. However, top management support was not related to PME. Synergy has the highest relative importance level in influencing PME and it is regarded as the most relevant construct for managerial actions.

This study examines the significant factors that contribute to the effectiveness of project management in the local councils. It forms a basis for other state local councils to emulate the research model and compare the findings among different project teams in different locations.

The IPMA identifies synergy as a primary important construct for project management activities. It explains PME is linked with extensive collaboration, inter-departmental relations, interpersonal coordination and close liaisons.

This study is among the few that examines factors influencing PME in the Malaysian local councils. Inclusion of synergy as one of the predictor constructs will definitely help to improve the well-functioning and coordination of the project.

Failures in both followership and leadership become inevitable as mega construction projects are directed and controlled by toxic leaders. Consequently, team member's desire for knowledge hoarding silence is triggered and goal alignment between the leader and team members suddenly fades away to realize success in mega projects. Considering the growing importance of these rarely examined constructs and fragmented literature on toxic leadership (TL), team silence and mega project success (PS) in the global construction industry, the present study aimed to examine the effects of TL and project team member's silence (PTMS) on the success of mega construction projects. Moreover, the mediating influence of PTMS to link TL and mega construction PS has also been explored.

Drawing on survey data of 326 project professionals directly associated with mega construction projects worth US$62bn under the China–Pakistan Economic Corridor (CPEC), the conceptual model was tested with covariance-based structural equation modeling (CB-SEM) using Mplus program. Scales were adapted from previous research to measure TL (with its five-dimensions including abusive supervision, authoritarian leadership, self-promotion, narcissism and unpredictability), PS (with its three-dimensions including project management success, project ownership success and project investment success) and project team members' silence. Reflective–formative second order assessments were specifically applied to measure the multi-dimensional nature of TL and PS, respectively.

Mplus estimations revealed that TL negatively influences PS, besides forcing a culture of silence among project team members. Interestingly, the relationship between TL and PS is also negatively mediated by the PTMS.

The present study's findings are derived from data of project professionals (N = 326) to examine success in megaprojects under the CPEC. Hence, these findings may be re-validated through future studies on similar megaprojects (e.g. China's Belt and Road Initiative (BRI) worth US$8tn) that may also be predicated by TL tendencies, silent cultures and high-stakes involved to seize PS.

Policymakers, construction practitioners and other key stakeholders (e.g. departmental heads/supervisors) can take advantage of this new evidence to better interpret the success paradox in mega projects, and to reduce the spread and long-term damage of TL on team members and eventually create opportunities for PS.

The present study's novelty is manifested within this first empirical evidence on TL that breeds team silence in underperforming mega projects. Notably, present study offers alarming evidence on mega projects that can be easily derailed from success, as they continue to suffer from team silence and TL.

This study examines the relationship between employees' perceptions of informational fairness and project performance. Furthermore, it examines if this relationship is sequentially mediated by (1) knowledge sharing and role clarity and (2) communication openness and role clarity.

Data are collected from 302 full-time employees of seven project-based construction organizations in Pakistan. Data are analyzed through variance-based structural equation modeling technique and the Preacher and Hayes' bootstrapping procedure.

Results indicate that project employees' perceptions of informational fairness positively predict project performance. Moreover, this relationship is sequentially mediated by (1) communication openness and role clarity and (2) knowledge sharing and role clarity.

This study provides further insights on the informational fairness and project performance relationship by examining their underlying mechanisms. It draws on the much ignored context of Pakistan, and offers some implications for managers and researchers with regard to how behavioral factors may further enhance project performance.

The purpose of this paper is to present a systematic review of studies on CPD published between 1985 and 2018.

Before identifying common CPD, research trends were examined in terms of the number of publications in selected journals, as well as the contributions made by countries, institutions and researchers.

The findings reveal that researchers from developing countries have contributed the most to identifying the causes of CPD. A total of 149 causes of CPD were identified in a thorough review of 97 selected studies. Weather/climate conditions, poor communication, lack of coordination and conflicts between stakeholders, ineffective or improper planning, material shortages, financial problems, payment delays, equipment/plant shortage, lack of experience/qualification/competence among project stakeholders, labour shortages and poor site management were identified as the ten most common CPDs.

Being the first study of its type, this study provides insight into the research output related to this area and identifies a common set of CPDs, which may provide a better understanding of the key areas requiring attention where steps should be taken to minimise or control factors causing delays in construction projects.

The study aims to find the causes of road projects implementation delays in Blantyre, one of the four city councils (CCs) in Malawi.

The study followed a qualitative research approach using a Blantyre City Council (BCC) as a case study. This study combined in-depth, face-to-face interviews with councillors, secretariat staff, consultants, and contractors who worked on the city's road projects. Data gathered were analysed using thematic content analysis. Also, some road project documents were examined.

The findings from the case study revealed the primary cause of road project construction delays as the shortage of engineers in conducting detailed proposed projects surveys resulting in incomplete project scope definition before contractor's procurement. Other identified factors were service providers delaying the removal of existing public utility infrastructure from project sites, client funding issues, scope changes, and client delays in issuing instructions to the contractors during project implementation. Another factor was the shortage of construction equipment and construction materials experienced by some appointed contractors.

Only road construction projects and stakeholders operating from Blantyre city, Malawi, were contacted for the study; thus, the findings may not be generalizable.

There is an urgent need to increase technical employees, especially engineers and other critical technical staff such as quantity surveyors in Blantyre. Employees' conditions of service should be conducive to attract qualified people to undertake effective management and assessment of projects before commencement to identify the feasibility of proposed projects to decrease the rate of road construction project delays.

The study has established Blantyre city's core challenges in implementing its road projects seamlessly and has provided mitigation measures for dealing with the shortcomings.

Construction projects in the real estate sector are important for a nation’s economic growth. However, owing to several constraints and stereotypes, the construction industry is suffering from major capital losses. A review of recent literature revealed that risks occurring in real estate construction projects (RECPs) carried out in developing economies can be divided into four categories, i.e. financial risks, design risks, execution risks and sociopolitical risks. This study aims to identify the critical factors that lead to these risk categories and develop a control structure for RECPs.

A quantitative method, i.e. a questionnaire-based survey, was used for this study. Using a random sampling technique the questionnaire was distributed to selected, highly experienced project managers. To determine whether the factors identified as part of the literature review strongly influence the categories, the factor analysis of the observations was performed.

The observations made in this study lead to the identification of six critical risk causing factors, i.e. lack of efficient planning, execution constraints, external constraints, client-induced constraints, project constraints and partner experience. The observations indicated a lack of knowledge of project management, organizational culture and a claims redressal mechanism in RECPs. Also, this study recommends a blockchain-based control structure to control the occurrence of the risk causing factors identified.

This study recommends a blockchain-based control structure for controlling the risks occurring.