Poor quality of design documents and Design Deficiencies (DDs) are critical factors that can potentially cause time and cost overrun and lead to project failure. Despite the…
Abstract
Purpose
Poor quality of design documents and Design Deficiencies (DDs) are critical factors that can potentially cause time and cost overrun and lead to project failure. Despite the importance of this issue, few studies have been conducted to explore the underlying relations among the causes and effects of DDs, and it is not clear how they exert influence on each other. However, it is imperative to have a clear understanding of their interrelationships so as to devise intervention strategies. The purpose of this study is, therefore, to explore these causes and effects.
Design/methodology/approach
To this aim, a qualitative system dynamics model was provided to visualize how various factors interact with one another. The model was developed and validated by drawing on the expertise of industry-related experts. The key causes and effects of the DDs were identified through the investigation of the model.
Findings
It was concluded that design management of project and the composition of design teams are critical. The obtained results also showed that more attention should be paid to the enhancement of knowledge circulation and communication within design firms and increasing the awareness of managers and owners from the technical consequences of their managerial decisions.
Research limitations/implications
It is worth mentioning that the design process could be deeply affected by the quality, frequency and strength of relationships among the project’s parties. Early involvement of contractors, for example, can significantly contribute to enhancing design quality. This study investigates factors’ interactions in projects delivered using the traditional design-bid-build method. As relationships between the project’s parties could be different in various project delivery methods, further research is indeed needed to assess factors’ interactions in projects delivered using other methods.
Originality/value
It is believed that the proposed model by providing a better insight into the connections of causes and effects could aid project managers of different parties with planning the strategies to reduce DDs and mitigate their effects.
Details
Keywords
Shahab Shoar, Nicholas Chileshe and Shamsi Payan
The purpose of this study is to investigate the latent interrelationships of causes and effects of design deficiencies (DDs) and to identify the most crucial ones by considering…
Abstract
Purpose
The purpose of this study is to investigate the latent interrelationships of causes and effects of design deficiencies (DDs) and to identify the most crucial ones by considering the interactions among them.
Design/methodology/approach
First, through a comprehensive literature review, the most critical causes of DDs were identified. The review eventuated in a list of 22 causes and 12 effects, which were categorized into six groups. Second, through the rules of system dynamics and the interactions between the causes and effects were modeled and illustrated using causal loop diagrams (CLDs). With the aid of semi-structured interviews with 20 competent experts, the resultant CLDs were also validated. Third, the opinions of 54 experts, who were chosen from the Iranian community of clients and consultants, were solicited concerning the degree of influence which each factor (causes or effects) exerts on others. Finally, the social network analysis (SNA) approach was deployed to analyze and prioritize factors based on the gathered data from experts.
Findings
SNA results indicated that factors such as “design firms' staff rework” and “design firms' loss of reputation” are the most central factors affecting DDs. The model results also identified that factors such as “schedule variance”, “workload” and “lack of quality control and supervision during the design phase” have the highest overall impact on DDs. In the end, some recommendations to address major factors and links were also put forward. Overall, more communications between the pair of stakeholder groups and continuous learning from project experiences are believed to be the main strategies.
Originality/value
It is believed that this study has provided a comprehensive understanding of causal mechanisms among factors, which can assist project managers of different parties (clients, contractors and consulting firms) in taking more effective actions to ameliorate the quality of design documents.
Details
Keywords
Shahab Shoar, Tak Wing Yiu, Shamsi Payan and Majid Parchamijalal
Although several studies have been conducted on the causes of cost overrun, they have mainly assumed that the causes of cost overrun are independent of each other, and few of them…
Abstract
Purpose
Although several studies have been conducted on the causes of cost overrun, they have mainly assumed that the causes of cost overrun are independent of each other, and few of them scrutinized the complex interrelationships between the causes. To fill the gap, this study aims to investigate the mutual interactions between the causes of cost overrun using interpretive structural modeling (ISM) and proposing strategies to tackle the causes considering their interactions.
Design/methodology/approach
Critical causes of cost overrun were identified through a comprehensive literature review. In total, 22 key causes are then refined based on the opinions of relevant experts involved in the Iranian building and construction sector. Using the nominal group technique, the causes' interactions were examined and represented via the ISM diagram. The causes were also classified using “matrix cross-reference multiplication applied to a classification (MICMAC)” technique.
Findings
The results showed that price fluctuation, claims, execution delay, delay in payment and change order positioned at the highest level of the obtained model can directly result in cost overrun, and corruption and poor contract management located at the base of the model are two major root causes of cost overruns. It was also concluded that more attention should be paid to the precontract phase of the project to address and prevent corruption and managerial issues deeply rooted in this stage.
Originality/value
The findings of this study provide a clear understanding of how different causes of cost overrun are related to each other and can ultimately assist project managers of different parties in choosing strategies to mitigate cost overrun in building construction projects.
Details
Keywords
Amin Shahsavar, Pouyan Talebizadeh Sardari and D. Toghraie
This paper aims to numerically investigate the heat transfer and entropy generation characteristics of water-based hybrid nanofluid in natural convection flow inside a concentric…
Abstract
Purpose
This paper aims to numerically investigate the heat transfer and entropy generation characteristics of water-based hybrid nanofluid in natural convection flow inside a concentric horizontal annulus.
Design/methodology/approach
The hybrid nanofluid is prepared by suspending tetramethylammonium hydroxide-coated Fe3O4 (magnetite) nanoparticles and gum arabic (GA)-coated carbon nanotubes (CNTs) in water. The effects of nanoparticle volume concentration and Rayleigh number on the streamlines, isotherms, average Nusselt number and the thermal, frictional and total entropy generation rates are investigated comprehensively.
Findings
Results show the advantageous effect of hybrid nanofluid on the average Nusselt number. Furthermore, the study of entropy generation shows the increment of both frictional and thermal entropy generation rates by increasing Fe3O4 and CNT concentrations at various Rayleigh numbers. Increasing Rayleigh number from 103 to 105, at Fe3O4 concentration of 0.9 per cent and CNT concentration of 1.35 per cent, increases the average Nusselt number, thermal entropy generation rate and frictional entropy generation rate by 224.95, 224.65 and 155.25 per cent, respectively. Moreover, increasing the Fe3O4 concentration from 0.5 to 0.9 per cent, at Rayleigh number of 105 and CNT concentration of 1.35 per cent, intensifies the average Nusselt number, thermal entropy generation rate and frictional entropy generation rate by 18.36, 22.78 and 72.7 per cent, respectively.
Originality/value
To the best knowledge of the authors, there are not any archival publications considering the detailed behaviour of the natural convective heat transfer and entropy generation of hybrid nanofluid in a concentric annulus.