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.
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Wenbao Wang, Iwan Harsono, Chich-Jen Shieh, Vadim Samusenkov and Shahab Shoar
Infrastructure projects play a vital role in the development of countries' economies. However, these projects, notably underground ones, are encountering growing claims as they…
Abstract
Purpose
Infrastructure projects play a vital role in the development of countries' economies. However, these projects, notably underground ones, are encountering growing claims as they are subject to many unknowns. Without having a clear insight into the causes of claims and their influence on one another, it is not possible to mitigate their adverse impacts on these projects' goals. To this aim, the main purpose of this study is to identify the critical paths leading to cost claims for underground metro projects.
Design/methodology/approach
First, causes of claims were identified through a literature review and then refined to 22 main causes according to the opinions of 148 Iranian experts. A qualitative system dynamics (SD) model was then provided to visualize how various causes interact with each other. The model was developed and validated by drawing on the expertise of industry-related experts, and the critical paths were finally recognized based on their frequency and severity indexes.
Findings
The findings revealed that each cause should be evaluated based on their connections with others as there are complex relations among the causes. It was also shown that the major claim paths among others were initiated due to ambiguous contract clauses, unforeseen physical conditions and land handover problems.
Originality/value
The findings of this study provide a better insight into how various causes of claims for underground metro projects are related to each other and can eventually assist project managers of different parties, even in other countries, to select proportional strategies to mitigate their adverse impacts.
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Majid Parchami Jalal and Shahab Shoar
This paper aims to model different causal relations among factors interacting with labour productivity in order to recognize the most important factors influencing and influenced…
Abstract
Purpose
This paper aims to model different causal relations among factors interacting with labour productivity in order to recognize the most important factors influencing and influenced by it.
Design/methodology/approach
Top 60 factors affecting labour productivity were determined and grouped into 5 major groups by reviewing previous research and interviewing relevant experts. The interactions of factors were modelled using system dynamics (SD) approach. The resulting causal loop diagrams obtained from SD were then applied for identifying the most crucial factors influencing and influenced by labour productivity through the decision-making trial and evaluation laboratory (DEMATEL) method. The impact of factors on each other was finally determined based on the opinions of 63 experts selected from the Iranian construction industry.
Findings
The results indicated that factors such as fatigue, lack of labour motivation and lack of skill are the most influencing, and factors such as schedule delay and inflation in the cost of execution are the most influenced by labour productivity. In the end, a set of recommendations to improve construction labour productivity was also presented.
Originality/value
The main contribution of the study is proposing a novel method which is capable of providing insights into how causes and effects of construction labour productivity are interrelated. Furthermore, the proposed method makes this study distinct from previous research in the light of prioritizing factors and offering recommendations according to the interrelationships among factors.
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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.
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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.
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Majid Parchami Jalal and Shahab Shoar
The purpose of this paper is to develop a model for complex interconnected structure of various factors interacting with delay in order to identify the most important factors…
Abstract
Purpose
The purpose of this paper is to develop a model for complex interconnected structure of various factors interacting with delay in order to identify the most important factors influencing and influenced by delay based on their interrelations.
Design/methodology/approach
Reviewing literature and interviewing with local experts selected from the Iranian construction industry, top 58 delay factors were identified and categorized into six major groups. The interrelations among these factors were, then, modeled using the system dynamics (SD) approach. The resulting causal loop diagrams obtained from SD were used subsequently for identifying the most significant factors influencing and influenced by delay through the Decision Making Trial and Evaluation Laboratory (DEMATEL) method. The impact of factors on each other was finally determined based on the opinions of 63 experts selected from the Iranian community of consultants, contractors, and clients.
Findings
According to the analysis, eight out of the 58 factors were identified as the most influencing factors on delay, and nine factors were found to be the most influenced factors by delay in the field of delay analysis. The study also concluded that factors related to labors are the most important and influential factors. In addition, factors related to client were the most influencing factors and external-related factors were the least important ones. At the end, some recommendations to reduce variation of delay in the construction projects are presented as well.
Originality/value
Considering the interconnected structure of the factors, the paper identifies the most important factors interacting with time delay in construction projects.
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Shahab Shoar, Farnad Nasirzadeh and Hamid Reza Zarandi
The purpose of this paper is to present a fault tree (FT)-based approach for quantitative risk analysis in the construction industry that can take into account both objective and…
Abstract
Purpose
The purpose of this paper is to present a fault tree (FT)-based approach for quantitative risk analysis in the construction industry that can take into account both objective and subjective uncertainties.
Design/methodology/approach
In this research, the identified basic events (BEs) are first categorized based on the availability of historical data into probabilistic and possibilistic. The probabilistic and possibilistic events are represented by probability distributions and fuzzy numbers, respectively. Hybrid uncertainty analysis is then performed through a combination of Monte Carlo simulation and fuzzy set theory. The probability of occurrence of the top event is finally calculated using the proposed FT-based hybrid uncertainty analysis method.
Findings
The efficiency of the proposed method is demonstrated by implementing in a real steel structure project. A quantitative risk assessment is performed for weld cracks, taking into account of both types of uncertainties. An importance analysis is finally performed to evaluate the contribution of each BE to the probability of occurrence of weld cracks and adopt appropriate response strategies.
Research limitations/implications
In this research, the impact of objective (aleatory) dependence between the occurrences of different BEs and subjective (epistemic) dependence between estimates of the epistemically uncertain probabilities of some BEs are not considered. Moreover, there exist limitations to the application of fuzzy set rules, which were used for aggregating experts’ opinions and ranking purposes of the BEs in the FT model. These limitations can be investigated through further research.
Originality/value
It is believed that the proposed hybrid uncertainty analysis method presents a robust and powerful tool for quantitative risk analysis, as both types of uncertainties are taken into account appropriately.
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Vahid Rooholelm and Abbas Sheikh Aboumasoudi
Almost all projects in the world are delayed, and sometimes even lead to the full bankruptcy of their beneficiaries. These delays can be calculated using techniques, but most…
Abstract
Purpose
Almost all projects in the world are delayed, and sometimes even lead to the full bankruptcy of their beneficiaries. These delays can be calculated using techniques, but most importantly, there must be a fair and realistic division of delays between project beneficiaries. The most valid delay calculation techniques belong to the SCL Global Protocol, but they also have significant drawbacks, such as these: (1) They do not have the capability to prevent project delays (Delay Risk Management); (2) The protocol identifies and introduces any delays in activities with a ratio of one to one as a delay (Effective Delay); (3) It also does not offer the capability to share delays between stakeholders, which is a huge weakness. Floating in the base schedule activities is one of the cost control tools of projects, but it can hide project delays. In this paper, the researchers believe that the floating ownership belongs to the project and not belong to the stakeholders. This is the main tool for analyzing and sharing delays in this research.
Design/methodology/approach
The research methodology adopted included an extensive literature review, expert interviews, use of questionnaire and designing three innovative linked together models by researchers.
Findings
In this research, an integrated technique is introduced which has the following capabilities; delay risk control, result-based delay analysis and stakeholders delay sharing. This technique with an incursive and defensive approach implements claims management principles and calculates, respectively, non-attributable and attributable delays for each beneficiary.
Originality/value
This creativity led to the introduction of the Incursive and Defensive (In-De) technique; in the SCL protocol techniques, none of these capabilities exist.