Construction is a labour-intensive industry. As poor productivity of construction labour is one of the causes of cost and time overruns in construction projects, it is of critical importance to the ...performance and profitability of construction projects and the overall economy of any country. This paper aimed to identify and rank factors affecting construction labour productivity in Yemen. A survey questionnaire was structured and distributed to architectural and structural engineers who were working on construction projects. The questionnaire included 52 predefined factors, which were categorized into four primary groups: human/labour, management, technical and technological, and external. The relative importance index (RII) was determined and the factors were ranked. The results showed that the group of technical and technological factors ranked first among the four groups. The top five factors identified were the most significant in their effect on construction labour productivity in Yemen: (1) labour's experience and skills, (2) availability of materials in site, (3) leadership and efficiency in site management, (4) availability of materials in the market, and (5) political and security situation. The findings of this study will provide awareness and a better understanding of factors affecting labour productivity in construction projects in Yemen.
The construction industry is a major sector in the economy of developing countries. During the last two decades in Algeria, many large-scale construction projects have been launched to develop the ...basic infrastructure facilities of the country. However, most of these projects experience extensive delays. The objective of this paper is to identify the causes of delay in the Algerian construction industry and assess their importance according to the main project stakeholders, which are the owner, the contractor and the consultant. Data were collected through a questionnaire and direct interviews of a sample of construction experts including 16 owners, 16 contractors and 20 consultants. Fifty-nine causes of delay were identified in this research. The results indicate that the five most important causes are slow change orders, unrealistic contract duration, slow variation orders in extra quantities, delays in payment of performed work and ineffective planning and scheduling by contractors. The study revealed that owner-related causes are the most important sources of delay. The findings of this research can be used to guide the improvements of the construction industry in Algeria.
Construction delays are a common phenomenon in civil engineering projects in Egypt including road construction projects. Therefore, it is essential to study and analyze causes of road construction ...delays. This paper studied a list of construction delay causes gathered from literature having different types of construction, different countries, different periods and different numbers of delay causes and delay groups. A questionnaire and personal interviews have formed the basis of this paper listing 293 delay causes. The questionnaire survey was distributed to 500 construction participants and 389 were received who represent consultants, contractors and site/design engineers excluding the owner representing the government in road projects as one party only. Relative Importance Index (RII) is calculated and according to the highest values the top twenty and the least twenty delay causes of construction projects in Egypt are determined. A case study is analyzed and compared to the most important delay causes in the paper. The test results reveal good correlation of causes and groups between contractors and site/design engineers and between consultants and site design engineers and a somewhat low correlation between contractors and consultants. So there are no root causes that can be taking for granted to be most or least effective delay causes. Proposed model for predicting actual road construction project duration was developed; a real case study tested the accuracy of proposed model. According to the analysis of case study, the most contributing causes and groups to delays were discussed, and some future recommendations were proposed in order to control and minimize delays in road construction projects. These findings can be helpful for project managers to mitigate the road construction delays in Egypt. In order to effectively overcome the road construction delays in developing countries, suggestions are made for fundamental and large‐scale reforms in procurement systems and stakeholders’ management. Also, this paper is useful for both researchers and road construction parties and allows detailed and repeatable analysis of the progress of a road construction project in order to facilitate and achieve a competitive level of time, cost and quality for effective road construction projects.
Automated monitoring technologies are being praised in the construction sector due to effective and efficient outcomes. However, hesitation remains towards its adoption, and one of the reasons is the ...lack of theoretical understanding towards effective implementation. This study aims to develop a theoretical framework highlighting the factors impacting the effective performance of automated monitoring. Overall, 36 factors were identified under four technological categories. The knowledge framework has been developed with the help of data collected by adopting a structured literature review, questionnaire-based survey, and statistical analysis techniques. The developed technological framework highlights the most impactful factors for each close-range automated monitoring process and technology. This study provides the base conceptual foundation to stakeholders towards the theoretical understanding of automated monitoring processes and technologies for factors that impact the outcomes.
AbstractConstruction labor productivity has become such a buzz word and one of the most frequently researched topics. In most countries, labor cost comprises 30 to 50% of the overall project’s cost, ...and thus is regarded as a true reflection of the economic success of the operation. There are many challenges facing the construction industry in the state of Kuwait but one of the most important is low productivity. The objective of this research, therefore, is to identify and rank the relative importance of factors perceived to affect labor productivity on construction sites in Kuwait. To achieve this objective, a statistically representative sample of contractors was invited to participate in a structured questionnaire survey, comprising 45 productivity factors, classified under the following four primary groups: (1) management; (2) technological; (3) human/labor; and (4) external. Among the factors explored, the subsequent 10 are discerned to be the most significant in their effects on labor productivity: (1) clarity of technical specifications; (2) the extent of variation/change orders during execution; (3) coordination level among design disciplines; (4) lack of labor supervision; (5) proportion of work subcontracted; (6) design complexity level; (7) lack of incentive scheme; (8) lack of construction manager’s leadership; (9) stringent inspection by the engineer; and (10) delay in responding to requests for information. The results obtained fill a gap in knowledge of factors affecting labor productivity in Kuwait, which can be used by industry practitioners to develop a wider and deeper perspective of the factors influencing the efficiency of operatives and provide guidance to construction managers for efficient utilization of the labor force, hence assist in achieving a reasonable level of competitiveness and cost-effective operation.
This study assessed the safety measures and operational challenges of inland waterway transport along the Oron - Calabar route. Observation and structured questionnaires were used for the collection ...of data. Quantitative data were analyzed using descriptive statistics, while qualitative data were coded and analyzed using the 4- point Likert scale, which was converted to a relative importance index (RII) for each factor posing a challenge to operators. The result showed Safety equipment was provided onboard boats by operators. The RII computed showed that boat and engine replacement (RII = 0.874) was the most challenging factor, while water hyacinth (RII = 0.418) was the most minor factor. Other challenges were frequent lousy weather conditions, high running costs, floating logs and debris, extortion by law enforcement agents, difficulty in making headway against the opposite current, high price of safety equipment, passengers’ refusal to adhere to safety measures, and poor berthing facilities in their order of impact. Proper funding and enforcement of safety measures are at this moment recommended.
•Expert and consumers opinion are considered to identify barriers to EV adoption.•A combined Fuzzy DEMATEL and RII method are effective to analyze barriers.•Cause and Effect barriers for EV adoption ...are identified.•EVs technical features and battery technology are the most influential barriers.•Charging facilities and EV price are the major barriers to the customer’s.
Electric vehicles (EVs) are introduced to mitigate air pollution, greenhouse gas (GHG) emissions and reduce the dependency on fossil fuels. But the present EV sales are not impressive in India compared with other countries. Previous studies have attempted to identify the challenges to EV adoption based on the opinions of experts or road users. But it is essential to study both expert and users’ perspectives to understand the actual scenario. In addition, the government of India announced a revised FAME II subsidy for EV purchase in 2021, which has an additional incentive on the purchase cost. Thus, this study aims to identify the key potential barriers based on expert and customers’ perspectives. For this purpose, data were collected from the potential experts who have rich experience in EV, and 361 samples were collected from the customers who visited the EV showroom for an inquiry and test drive in Ahmedabad city, India. This study adopted the fuzzy DEMATEL method to identify the potential barriers based on expert opinion data and the Relative Importance Index (RII) method for prioritizing the barriers based on customers’ perspectives. The results show that the Higher initial purchase cost of a vehicle, Many EV manufacturers are new companies, Technical specification of the vehicle (power, acceleration, etc.), Less Mileage on a full charge of a battery, Non-Reliable battery technology, Lesser Adaptive competitive vehicle design, Limited availability of local technician, Limited availability of public charging stations, Higher waiting time at charging station if many vehicles are there, Safety concern while charging, Non-availability of charging facility on a long trip, and lack of understanding of subsidy policies (vehicle purchase subsidy and other EV incentives by government) are the major significant barrier in each group. Also, the revised FAME II subsidy policy and improvement on charging facilities have a significant positive effect on EV adoption. The outcome of this study will help the transport planners to develop necessary infrastructure facilities to boost EV. Also, this study outcome will help the EV policy makers and manufacturers to understand the consumer requirements.
AbstractConstruction delays are common in construction industry and create major concerns for project performance. Construction delays are caused by many factors. The aim of this paper is to identify ...delay factors on construction projects and analyze these factors with the relative importance index method. For this purpose, 83 different delay factors were identified, categorized into nine major groups, and visualized by the Ishikawa (fishbone) diagram through detailed literature review and interviews with experts from the construction industry. The relative importances of these delay factors were quantified by the relative importance index method. The ranking of the factors and groups were demonstrated according to their importance level on delay. According to the case study results, the factors and groups contributing the most to delays (those needing attention) were discussed, and some recommendations were made to minimize and control delays in construction projects.
Tunnel construction is considered a bottleneck point in mega construction projects because of higher associated risks and uncertainties. This study is an attempt to identify and rank the causes ...project overruns in tunnel construction projects in Pakistan and propose a mitigation strategy to minimize their effects. For the given purpose, a total of 32 key causes were obtained from the literature and discussion with a team of experts and practitioners. A web-based questionnaire survey was used for data collection. About 55 complete responses were received from the practitioners working as clients, consultants, and contractors in Pakistan. The identified causes were ranked using frequency, severity, and relative importance indexes. The most important causes were found to be inexperienced and incompetent contractors, ignoring consultants' instructions by contractors, inadequate project estimates, delay in issuance of funds to the contractors, and low bids. This study can be employed for controlling the leading causes of overruns in tunnel construction projects. Moreover, it can serve as a guide in further investigation of the causes of project overruns in tunneling in different countries.
Construction projects are highly complex and dynamic in nature. However, its dynamicity subjects it to several delays and risks; before, during and after construction. Therefore, it is paramount to ...identify the possible sources of delays and risks so as to prioritize them. This study used a literature review and perception of construction professionals in the Indian construction industries to assess and prioritize delays and risks. Statistical analysis using relative importance index and fuzzy ranking was employed to identify, assess, and prioritize delays and risks in the Indian construction industry context. Inadequate schedule was found to be the most critical risk, which constitutes a long-term problem in any construction projects. New risks were identified in the tendering stage. It is anticipated that the result of this study would be a guidebook for all stakeholders in the construction industry to assess and prevent any possible delay and risk in their construction processes.
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