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91.
This paper investigates the impact that integration can have on teamwork effectiveness within construction project delivery teams. The level of team integration was assessed within selected award-winning delivery teams of completed projects. A similar assessment was made of teamwork effectiveness achieved within the same project teams. The findings of this research reveal that teams with different levels of integration had the same or similar levels of teamwork effectiveness. Thus whilst integration is desirable, it is not the only requirement or condition for improved teamwork within a construction sector context. The findings suggest that the role and value of integration in project teams is unclear relative to other performance enhancing approaches. Further research is recommended to identify the factors and conditions that influence the direct impact of integration on teamwork effectiveness within the project delivery team.  相似文献   
92.
探讨了澳大利亚CSIRO型空心包体式钻孔三向应变计的测量技术,重点介绍了测量元件应变片的布置形式和利用围压加载试验成果修正原始解除应变实测值的方法。对解除应变实测值的修正提出了具体方法,由修正后的解除应变推算的地应力实测值更精确。在三峡工程永久船闸开挖完成后岩体应力动态变化测量中,具体分析了测量元件应变片黏贴部位和角度的误差所引起的地应力实测值的误差,具体实施了对解除应变实测值的修正,实测的岩体应力动态变化更符合工程实际情况。  相似文献   
93.
 当前TBM在深埋隧洞施工中的应用越来越多,由变形引起的TBM施工事故也越来越普遍,因此很有必要对变形引起的TBM施工事故进行风险分析。采用收敛–约束法并结合风险分析理论,考虑洞室的掌子面和护盾后方支护的效应,对围岩作用在护盾上的压力进行计算;同时,根据作用护盾上压力大小判断洞室变形对TBM施工的具体影响,把事故的后果分为5个等级,根据后果等级结合发生的概率提出TBM施工变形风险评价矩阵,然后结合现有的风险接受准则即可确定风险等级。最后,采用研究成果对南水北调西线某段双护盾TBM施工进行风险评估。  相似文献   
94.
This paper presents the development of a novel probabilistic scheduling model that enables fast and accurate risk evaluation for large-scale construction projects. The model is designed to overcome the limitations of existing probabilistic scheduling methods, including the inaccuracy of the program evaluation and review technique (PERT) and the long computational time of the Monte Carlo simulation method. The model consists of three main modules: PERT model; fast and accurate multivariate normal integral method; and a newly developed approximation method. The new approximation method is designed to focus the risk analysis on the most significant paths in the project network by identifying and removing insignificant paths that are either highly correlated or have high probability of completion time. The performance of the new model is analyzed using an application example. The results of this analysis illustrate that the new model was able to reduce the computational time for a large-scale construction project by more than 94% while keeping the error of its probability estimates to less than 3%, compared with Monte Carlo Simulation methods.  相似文献   
95.
This paper follows “Construction Engineering: Reinvigorating the Discipline.” That paper argued that a new flow-based operating system was poised to replace the activity-centered operating system of traditional project management and that a coherent organizational and contractual approach would evolve. Shifting to a new operating system based on the theory, principles, and practices of production system design will reduce waste, spur learning and innovation, and deliver more value to clients and other participants. After a reflection on a model for making sense, the paper explores the consequences of this shift from a number of perspectives and speculates on the impact on practice and research. The paper closes with a brief reflection on teaching in times of rapid change.  相似文献   
96.
Selecting an appropriate delivery method that will achieve a project’s objectives and characteristics is one of the most critical factors for the project’s success. A selection model for this study was developed by using actual construction case data in quantitative data analysis methods such as logistic regression, factor analysis, and correlation analysis. The model was developed on the basis of the design-build and design-bid-build methods from various project delivery methods. To validate the developed model, comparative tests were conducted on the selection of the delivery method for multifamily-housing construction projects, which showed that the model resulted in 95.0% accuracy. It is expected that the developed selection model will enable owners to select delivery methods that accurately meet their needs characteristics, project characteristics, and external environments.  相似文献   
97.
Environmentally sustainable building construction has experienced significant growth during the past 10 years. The public is becoming more aware of the benefits of green construction as prominent politicians, celebrities, documentarians, and journalists highlight the built environment’s impact on greenhouse gas emissions and natural resource consumption. Other factors, including higher energy prices, increased costs of building materials, and regulatory incentives, are also pushing the green building market to grow and expand. However, barriers to green building continue to exist, including the ability to deliver a green project within acceptable cost constraints. In order for project managers to deliver sustainable construction according to clients’ cost expectations, modifications must be made to traditional project management processes and practices. The objective of this paper is to suggest specific modifications to conventional building practices to optimize the delivery of cost-efficient green building projects. This paper presents an overview of research related to the costs and trends of green building and uses these research findings to make recommendations for greening project management practices for the construction industry. Our research results show that greening project management practices can add significant value to a sustainable construction project while delivering it within acceptable cost constraints. A detailed analysis using matrix present specific adjustments to traditional project management practices, with a premise that a green project improves its chances for financial success if a cross-discipline team is involved at the earliest stages and throughout the project.  相似文献   
98.
Infrastructure projects have major effects on implementing the principles of sustainable development. Infrastructure projects will continue to be developed in the coming years, particularly in developing countries such as China and India; therefore, it is important to find methods and solutions for improving the sustainability of them. Although existing studies have suggested various methods for practicing sustainable development principles in the process of implementing infrastructure projects, effective assessment indicators are unavailable, which presents a barrier to the effective assessment of infrastructure project sustainability. This study introduces key assessment indicators (KAIs) for assessing the sustainability performance of an infrastructure project. The research data used for analysis were collected from a questionnaire survey given to three groups of experts, including government officials, professionals, and clients in the Chinese construction industry. The fuzzy set theory was used to establish KAIs. A procedure for using the KAIs is demonstrated by a case study. These research findings provide an alternative solution to appraise the sustainability of infrastructure projects.  相似文献   
99.
Departments of transportation in the United States are under increasing pressure to accelerate projects to meet user-defined constraints and reduce the inconvenience to the traveling public. Although there is information about acceleration projects in other industries, there has been little specifically aimed at highway projects. A domestic scan sponsored by the National Cooperative Highway Research Program was tasked with providing information in this area. The objective of this paper is to synthesize the resulting information into fundamentals that support successful planned accelerated highway project delivery. Case studies of how departments of transportation successfully accelerated the construction of four very different projects in California, Florida, and Texas serve as the basis for identifying these fundamentals. The fundamentals include upfront and detailed planning, designs that facilitate accelerated construction, a collaborative environment for project stakeholders, and incentives and disincentives to motivate construction contractors.  相似文献   
100.
三峡水利枢纽工程是治理开发长江的关键性工程,承担着防洪、发电、航运等综合利用任务。工程建成后可确保荆江地区防洪标准不低于百年一遇,大大缓解长江中下游防洪压力,为经济建设发展迅速的华中、华东、华南地区提供巨大的能源支持,从根本上改善川江航运条件,同时枯季补偿调节可提高长江中游河段航道水深和改善航运条件。新时期,长江治理、开发与保护对三峡工程运行提出了新要求,如何优化水资源利用,实施科学调度,全面提升水库综合效益,是三峡工程今后面临的一项长期任务。  相似文献   
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