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1.
The rapid growth of the Indian construction sector over the last few decades and recurring failure in on-time delivery highlight the need for a systematic analysis of the factors influencing delay. A theoretical structural equation model representing the influence of four key latent variables on project delays in the Indian construction industry has been developed. Data collected from a questionnaire survey and personal interviews, with 77 valid responses from clients, contractors and designers or architects, were used to further formulate and analyse the model. The results of the structural equation model suggest that client’s influence is one of the most significant factors affecting time performance on Indian projects. Client’s influence is also found to be one of the key contributing factors resulting in lack of commitment and contractor’s inefficiency in the project. Lack of efficient construction planning plays the second key role in adverse time performance. While the effect of lack of commitment on contractor’s inefficiency is highly significant, neither of these two factors has any direct impact on time delay in projects. Contrary to the notion that the contractor is the only party responsible for delay in construction projects, the results clearly highlight the importance of the role of clients and technical expertise in planning in achieving satisfactory time performance on Indian projects. It is hoped that these research findings will contribute significantly to the Indian construction industry’s efforts in addressing the root causes of delay and enhancing the time performance on projects.  相似文献   

2.
Delay is a common problem in the construction industry and there are several reasons that can contribute to delaying a project. In Hong Kong, completion of fire services installation is prerequisite to completing/finishing a building construction work. The fire services installation must be completed for application of an occupation permit for a building. Fail to obtain the permit on time would lead to construction delay. Apparently, fire services contractors play an important role in obtaining the occupation permit for a project completion. The economic losses due to construction delay could be very significant. This research identified, from a list of 49 pre-determined factors in nine categories (shown in Appendix A), the principal factors contributed to construction delays in a fire services installation. In particular, a questionnaire survey of 52 fire services contractors and 32 consulting engineers was conducted in order to obtain their professional judgements about the relative importance of the contributors of construction delay related to the fire services installation. The result showed that the principal contributors were: (1) improper site co-ordination and management of the electrical and mechanical installations, (2) lack of timely decision making of the client, and (3) defects identified during the fire services inspection by local authorities. In addition differing views were found between the consulting engineers and contractors on the areas identified were: (1) site management and supervision, (2) workload of the project staff, (3) the procedures for equipment approval, and (4) working experience of the parties. A monitoring and quality assurance system would be required in these areas to minimize the risk of the probable construction delay.  相似文献   

3.
Building industries in many countries have been increasingly recognising the need for more efficient and timely completion of projects. Often, a number of unexpected problems and changes from original design arise during the construction phase, leading to cost and time overruns. Therefore, exploring the reasons for delay is one of the prerequisites of keeping the cost within budget and of good construction time performance. The primary objective of this paper is to identify the principal factors responsible for delays in the Hong Kong building industry, and determine their relative importance as perceived by different participant groups. A questionnaire survey, based on 83 previously identified delay factors, grouped into eight major factor categories, was conducted in early 1995. Responses from 78 construction personnel — from client, consultant and contractor organisations — suggest a strong consistency in perception between clients and consultants, for example as to the importance of the “poor site management and supervision” delay factor and the “contractor-related” delay factor category. However, there was a substantial disagreement between consultants and contractors, as well as between clients and contractors, in respect of the rankings of both the individual factors and the factor categories. Suggestions are given for more effective project management based on the observations. The results of this survey also provide a foundation for further research towards the development of an envisaged “construction time” prediction model for local building projects.  相似文献   

4.
Construction projects continue to suffer delays. Things go wrong and the project's completion date gets pushed back, with someone to be blamed for it. In practice, attempts are made to identify the causes of delays and schedules are modified to incorporate revised duration and new project time. The analysis itself is usually complex and can be aided by a computerized approach. This paper discusses different delay analysis techniques that are currently used by practitioners in the construction industry. It also discusses a proposed new delay analysis technique called the Isolated Delay Type (IDT). These techniques were tested against a case example and their strengths and weaknesses highlighted. The new technique can be used as a standalone module for delay analysis or could be incorporated within a computer system for construction delay analysis and claims preparation called Computerized Delay Claims Analysis (CDCA) that integrates different software including an expert system and management software such as scheduling and a database or spreadsheet.  相似文献   

5.
Construction delay is considered one of the most recurring problems in the construction industry. Delays have an adverse impact on project success in terms of time, cost, quality and safety. The effects of construction delays are not confined to the construction industry only, but influence the overall economy of a country like UAE, where construction plays a major role in its development and contributes 14% to the GDP. Thus, it is essential to define the most significant causes of delay in order to avoid or minimise their impact on construction projects. A detailed questionnaire was developed and used to get input from professionals associated with the UAE construction industry. The perspective of contractors and consultants has been analysed to rank the causes of delays based on their Relative Importance Index. Contractors and consultants were in agreement on the most significant causes of delays. The research revealed that 50% of the construction projects in UAE encounter delays and are not completed on time. The top 10 most significant causes of construction delays have been identified by this research. Approval of drawings, inadequate early planning and slowness of the owners' decision‐making process are the top causes of delay in the UAE construction industry.  相似文献   

6.
多事件交叉干扰下的工期索赔方法   总被引:12,自引:0,他引:12  
在工程施工过程中,工期延误是很常见的,产生的原因也非常复杂,因此工期延误的责任归属和责任定量化对于索赔非常重要。针对多事件交叉干扰下工期延误引起的工期索赔责任归属难以判断和责任比例难以测量的问题,通过分析初始事件原则、不利于承包商原则和责任分摊原则的索赔处理机制以及网络计划的计算方法,提出一种程序化计算方法,即通过设置一系列易于嵌入计算机程序的变量,无需进行关键路线的分析,即可对各工序对于工期延误造成的影响进行较为精确的分析和排序。  相似文献   

7.
Delays in construction projects are inevitable and, as a result, claims and disputes arise. Different causes of delay can come into play and therefore the need to identify and classify different causes of project delay arises. Different factors that contribute to project delay affect the likelihood of project delay in different degree of effectiveness. Fuzzy fault tree analysis (FTA) is suggested by this research to estimate the likelihood of project delay. Likelihood of delay membership function is further quantified using the weighted average defuzzification method. Two fuzzy logic models are implemented into the fuzzy FTA, using Visual Basic software: the models discussed in this research are Baldwin's rotational model and the Angular model. Comparison between the two fuzzy logic models has been carried out. Validation of the fuzzy FTA computer model is performed. Validation of the model was performed for adequacy and applicability of the model. On average, the validation performed by independent construction engineers and fuzzy logic experts produced satisfactory results. The computer software suggested by this study is an attempt to assess the likelihood of the project delay, which helps reduce delays in construction projects that can cause time loss.  相似文献   

8.
建设项目中的工期延误影响因素研究   总被引:14,自引:0,他引:14  
在国内外的建设项目中,工期延误现象极其普遍。本文在阅读大量国内外文献的基础上,通过归纳总结、对比分析等研究手段,进一步分析工期延误的影响因素:进行了工期延误影响因素的分类研究;收集文献中的各类延误原因,并将收集到的12个国家和地区工程建设中的工期延误原因进行了统计分析,发现不同国家背景下的工期延误有各自的特点,总结了工期延误的重要原因。在研究中,本文还发现,不同工程的工期延误原因也有各自的特点并就工期延误问题提出了几点建议。  相似文献   

9.
Construction delay has become endemic in Nigeria. It is imperative to create awareness of the extent to which delays can adversely affect project delivery. This paper identifies, by questionnaire evaluates and through empirical method assesses the effects of construction delays. The findings showed that time and cost overruns were frequent effects of delay. Delay had significant effect on completion cost and time of 61 building projects studied. Client-related delay is significant in Nigeria. Acceleration of site activities coupled with improved clients' project management procedure and inclusion of appropriate contingency allowance in precontract estimate should assuage the adverse effect of construction delays.  相似文献   

10.
The availability of resources such as workforce and materials at each level of a high-rise construction project just before the commencement of building tasks is a crucial issue that might have direct impacts on project progress. To avoid delays caused by lack of human resources and construction materials, a construction management team always tries to find a better way to facilitate supply chain process specifically for construction projects facing a significant number of simultaneous and repetitive tasks. The other challenge in a high-rise construction project is vertical transportation that requires special machinery e.g. cranes or lifts, and also, maximizing their utilities. In this paper, it is tried to automate vertical transportation planning process in high-rise construction projects by introducing a platform that handles the entire lifting process. This platform considers (i) tasks attributes (e.g. required resources, location and commencement time) from the project schedule, (ii) lifting system specifications (e.g. travel speed, weight, and volume capacity) and (iii) project geometrics (e.g. current height of the project). In details, the introduced platform provides an optimized daily delivery plan by developing a Mixed-Integer Programming (MIP) model that covers workforce and construction materials. In this paper, the proposed platform is also tested using field data obtained from a 34-story construction project in Mashhad, Iran. The model could find a solution with 0% optimality gap in approximately 1 h, which is an acceptable amount of computational cost for the problem. The results show how the introduced platform can assist the construction management team to efficiently handle the supply process within stories while avoiding delays caused by a lack of resources required for each task.  相似文献   

11.
Assessing schedule delay's impact on total project duration to distribute delay liability remains a controversy. None of existing delay analysis methods is perfect because including an element of assumptions, subjective assessment and theoretical projection. Windows-based delay analysis methods are excellent in identifying and measuring construction schedule delays. Based on a previous study identifying potential problems in available windows-based delay analysis methods, this study proposes an innovative windows-based delay analysis method, called the effect-based delay analysis method (the EDAM method). The EDAM method performs delay analysis using extracted windows and determines delay impacts by considering the effects of delays on the critical path(s). According to its application to hypothetical cases and comparisons with other methods, the EDAM method is efficient in delay analysis and effective in solving concurrent delays and determining schedule shortened. The proposed EDAM method is a good alternative for schedule delay analysis for construction projects.  相似文献   

12.
The likelihood of a project delay is affected by different factors; thus, there is a pressing need to develop a method that estimates the likelihood of such a delay. In this paper, analysis of potential occurrences of delays, which are classified into procedural, enabling, and triggering causes, is performed using the fuzzy fault-tree analysis method. Subjective judgment expresses causes of delay and their respective degree of effectiveness which are analysed in this study. The fuzzy triangular model and translational models are employed in this study. The severity of the likelihood of the project delay is the result of this analysis. A model was developed to assess the likelihood of the project delay. Evaluation of the model was performed for applicability and adequacy of the model. On average, evaluation performed by independent construction engineers and fuzzy logic experts produced satisfactory results.  相似文献   

13.
Building project management requires effective coordination and collaboration between multiple project members. It can be achieved through real time communication flow between all. In present scenario, it can be achieved through adoption of Information and Communication Technologies (ICT). Construction industry primarily comprises small and medium enterprises (SMEs). Also, ICT adoption has been slow in the industry. Research is required to assess the factors that affect ICT adoption at the three levels of industry, organization and people, with focus on SMEs. This paper discusses a component of the research undertaken to study these factors and issues in the context of Indian construction industry. A questionnaire survey was conducted and through quantitative data analysis the extent of adoption of formal Project Management processes, ICT adoption for these processes and factors including perception based factors affecting ICT adoption were studied. Results of data analysis includes identification of issues that require action at the three study levels. The results can be generalized for other countries with due considerations, specifically for countries where the construction industry is similar to Indian construction industry in terms of working methodologies or for large countries.  相似文献   

14.
This study focuses on cost and schedule issues of international development (ID) projects. Through empirical analysis we examine ID project cost and schedule performance and the main reasons for poor project outcome. We look at 100 projects that are sponsored by the Asian Development Bank and hosted by several Asian countries. The study identifies that most late projects experience cost underrun – an unusual cost and schedule variation relation in projects. Further we identify the root causes of project delay and cost underrun. Research findings will benefit ID project professionals, organizations and the ID project body of knowledge. The study can be extended to analyse other developing country projects sponsored by different donors.  相似文献   

15.
Delay in the delivery of materials and equipment to construction sites is often thought of as a contributory cause of cost overruns in construction projects in developing countries. A cursory examination of the environment in which projects are executed in developing countries appears to support this thinking. However, there does not seem to have been much research work conducted that investigates whether this is actually the case and also assesses the causes of these delays and magnitude of their impacts on project costs. This research was aimed at firstly ascertaining the occurrence of material and equipment procurement delays in highway projects in Nepal. An assessment of the causes of the delays and the magnitude of their impact on project costs was also made. The survey method was used in conducting this research involving 22 highway projects. The main causes of material and equipment procurement delay were found to be (in rank order) organizational weaknesses, suppliers' defaults, governmental regulations and transportation delays. However, the actual impact of these delays on project costs was found to be on average, only about 0.5% of the total budgeted cost of the projects. Among materials, delays in the supply of aggregates were found to occur most frequently while delays associated with pavers occurred most frequently among equipment.  相似文献   

16.
Rework has been a primary cause of cost and schedule overruns in large construction projects. While several research efforts have analyzed the causes and effects of rework and provided guidelines to reduce rework, almost no research exists to analyze the impact of rework timing and quantity on schedule delays and to support decisions on cost effective recovery. This research presents a quantitative mechanism for schedule analysis considering rework. The mechanism has three aspects: (1) a new schedule representation of rework magnitude as negative percentage complete for affected activities, documented on the specific date on which the rework is detected; (2) a modified daily-windows delay analysis to apportion project delays among the responsible parties; and (3) an optimization technique for determining the least costly corrective action strategy that recovers project delays. The proposed approach is applied to a case study to demonstrate its ability to consider rework impact, in combination with other progress events by other project parties. This research offers an innovative quantitative approach to consider rework timing and amount in delay analysis and corrective action optimization.  相似文献   

17.
While construction industry practices are reasonably well developed, construction projects still witness widespread failures of many contractors due to varied reasons such as financial problems, poor management, over‐commitment and or conflicts and disputes associated with construction activities. Pre‐qualification of contractors is a common practice across projects, yet the investigation on the ability of the selected contractors in successful delivery of projects is not widespread. In an attempt to understand these pre‐emptive qualification criteria and their links in contractors’ performance in projects, a total of 43 influencing technical attributes were identified through a systematic research approach. The relative significance and impacts of the attributes have been determined based on a structured questionnaire survey in selected construction projects. By performing the factor analysis, a total of seven factors significant to contractors’ performance were extracted, namely (1) soundness of business and workforce; (2) planning and control; (3) quality management; (4) past performance; (5) risk management; (6) organizational capability; and (7) commitment and dedication. Multiple linear regression models reveal that technical expertise, past success, time in business, work methods and working capital significantly impact on contractors’ performance across time, cost and quality success. With a clear understanding of a contractor’s performance, these findings could potentially contribute to development of a company’s procedures or enhance existing knowledge in relation to the pre‐qualification practices in contractor selection in projects.  相似文献   

18.
The so-called ‘nuclear renaissance’ in Europe is promulgated by the execution of two large engineering projects involving the construction of two European Pressurized Reactors (EPRs) in Flamanville, France and Olkiluoto in Finland. As both projects have faced budget overruns and delays, this paper analyses their governance and history to derive lessons useful for the construction of future projects. Analysis indicates that the reasons for these poor outcomes are: overoptimistic estimations, first-of-a-kind (FOAK) issues and undervaluation of regulation requirements. These pitfalls have the potential to impact on many other engineering construction projects and highlight fruitful areas of further research into project performance.  相似文献   

19.
The success of construction projects is a fundamental issue for most governments, users and communities. In the literature that deals with construction project success and causes of time and cost overruns in the construction industry, there is some literature that highlights the role of the contractors in project success. While most studies rank contractors’ success attribute from tendering, prequalification, and a long term historical perception perspective, this paper aims to study the impact of contractors’ attributes on project success from a post construction evaluation perspective to identify what critical success factors (CSFs) that greatly impact the success of project. In an attempt to understand and investigate this impact, a questionnaire survey is used to establish construction professionals’ perception of CSFs of contractors that greatly impact on the success of construction projects. Factor analysis reveals nine underlying clusters namely :(i) safety and quality; (ii) past performance; (iii) environment; (iv) management and technical aspects; (v) resource; (vi) organisation; (vii) experience; (viii) size/type of pervious projects; and (ix) finance. Logistic regression techniques were used to develop models that predict the probability of project success. Factors such as turnover history, quality policy, adequacy of labour and plant resources, waste disposal, size of past projects completed, and company image are the most significant factors affecting projects success. Assuming that project success is repeatable, these findings provide clear understanding of contractors’ performance and could potentially enhance existing knowledge of construction project success.  相似文献   

20.
Previous research suggests that a characteristic of the construction industry is a lack of technological innovation. Since this is seen as a problem, much theoretical development within construction management focuses on explaining the lack of innovation. Less effort has been expended on using such explanatory theories for investigating those rare exceptions in which construction firms succeed in the unlikely: successfully developing a new technology. This article makes use of the recently suggested framework by Dubois and Gadde. They describe the construction industry as a ‘loosely coupled system’ with four types of couplings, discuss why the particular mix of couplings in the construction system leads to a lack of innovation, and suggest types of couplings that construction firms should experiment with and change in order to boost innovation. A case study of a contractor developing a new technology is presented in terms of Dubois and Gadde's concepts and implications. The findings partly support and partly contradict their hypotheses. It seems that innovation is possible even if only a few of the existing couplings are changed. The most important changes relate to the tightening of intrafirm sequential inter‐project couplings enabling learning from project to project, and contract‐related couplings especially the design‐construction interface.  相似文献   

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