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61.
结合工程实例,分析了施工现场安全事故发生的原因,针对这些建筑安全事故原因,提出了解决施工现场存在问题的相关对策,从而有效预防及减少建筑安全事故的发生,使施工企业更好地发展。  相似文献   
62.
建筑工程繁多的施工工艺、工序间的交叉作业及施工现场作业环境的复杂多变等因素共同导致建筑行业是安全事故频发的主要行业。因此,建筑工程施工安全管理工作受到越来越多的关注,合理的建筑工程施工安全管理投入对施工单位做好建筑工程施工安全管理具有十分重要的实践意义。在阐述建筑工程施工安全管理投入概念的基础上,从经济学的角度对建筑工程施工安全管理投入进行量化分析,构建建筑工程施工安全管理投入的量化模型,合理、客观地计算建筑工程施工安全管理投入,并结合实例进行了分析。  相似文献   
63.
Measuring construction productivity in an accurate, repeatable and reliable way represents a significant problem at a building project level of enquiry. The research develops a measurement framework that balances simplified data gathering against explanatory ability. It aims to assist analytically driven process improvement. Debate and discourse are used to draw upon the extant literature in creating a logic-based flow of ideas to develop the framework. Targeted use of empirical cost and site process data from case studies are presented to punctuate the discourse. The derived approach advocates multifactor measurement inclusive of labour and temporary production infrastructure inputs, set against Gross Floor Area outputs. Emphasis is placed on separately measuring homogenous and heterogeneous parts of work processes. A reductionist approach is used to operationalize measurement where projects are categorized according to fitness-for-purpose criteria and links made between systems, activities and tasks. Emphasizing measurement of homogenous parts of the work is new to the literature. It enables delineated measurement between work involving mass economies of scale (homogenous work), versus customized work (heterogeneous work). The approach enables improved benchmarking, diagnostic and predicative options. A course of ongoing research is provided to assist ongoing development and implementation.  相似文献   
64.
During the operation stage of public-private partnership (PPP) projects, investors may engage in opportunistic behaviour in pursuit of their own profits. In order to curb this kind of behaviour, this article analyses the selection of government supervision mode based on evolutionary game theory taking the perspective of government supervision. The results show that government supervision mode is closely related to the probability of identifying investors’ speculative behaviour through outcome-oriented supervision. When the probability of identifying such behaviour is relatively high, the equilibrium strategy of investors and governmental supervision institutions is (not to behave opportunistically, outcome-oriented supervision). In contrast, if the probability is relatively low, there is no set of evolutionarily stable strategies (ESS); rather, a periodic behavioural pattern is formed. In this scenario, the strategies ultimately chosen by both sides relate to initial states and the payoffs of the options. Furthermore, determinants and some recommendations for government supervision are proposed, providing a reference for efficient governance.  相似文献   
65.
It is often argued that integrated design (ID) is a powerful way to enhance collaboration in construction projects. This collaboration is seen as a way of improving innovation to create more sustainable buildings. Contrary to the traditional silo-type and linear design process, ID is based on upfront stakeholder involvement and a holistic approach to project decision-making. Although ID’s premises are theoretically-founded, a close empirical look at its practices shows that numerous challenges compromise its results and efficiency. This study examines the ID process through an iterative process that includes the construction of a conceptual framework and its empirical validation. We examine three green construction projects in Canada. Based on the analysis of 26 interviews with key project stakeholders and more than 198 construction documents, the study assembles – and ultimately applies – a multi-lens framework based on four themes: the fragmented nature of construction; risk perception; stakeholders’ commitment; and efficiency in the design process. Results show that three tensions arise in ID practices: between collaboration and process efficiency, between short-term and long-term goals, and between integrated methods and traditional ones. The study sheds light on ID limits and reveals how stakeholders can improve their interactions to design more sustainable buildings.  相似文献   
66.
Public–private partnerships (PPPs) involve many different participants, and the equity allocation between them may influence the performance of PPP projects. While the optimal capital structure and equity capital structure of the project company have been extensively investigated, few studies have examined how to allocate equity shares among different private participants. Considering both public and private benefits, this study focuses on the optimal equity structure between construction contractor (CC) and operating contractor (OC). A game model is used to analyze how quality benefit and marginal contribution of CC and OC’s effort affect the optimal equity structure. The findings reveal that the private consortium expects the party (CC or OC) with higher marginal contribution of effort to own more equity shares, while government expects the party (CC or OC) with lower marginal contribution of effort to own more equity shares. Furthermore, a non-linear relationship between the optimal equity structure and government’s bargaining power is found. The results also manifest that the quality benefit of construction on operation is a nontrivial factor when designing the equity structure. If unconsidered, the CC’s optimal equity ratio will be either undervalued (when a higher construction quality can reduce the operating cost) or overvalued (when a higher construction quality can increase the operating cost). These findings can provide some insights into designing the equity structure for PPP projects in the bidding process.  相似文献   
67.
This paper investigates project changes and their relationships with stage iteration and multi-functional interaction. Changes often occur in a complex solution-based project, which makes the linear management model limited in its application. Complex project planning is based on assumptions about future events. Assumptions often fail and as a result the plans contain activities that are impossible or unnecessary to execute. The consistency of project planning needs to be restored and maintained by revising or redefining project activities.  相似文献   
68.
In project teams that are distributed across the international subsidiaries of a firm, collaboration can be a challenge. The organizational context of projects is not always conducive to international collaboration. Priorities and interests of sub-teams are likely to differ from those of the central team. In a grounded theory study of international client projects in a project-based organization, the impact of organizational context on collaboration is explored. It was found that the organizational context can provide important resources such as authority, policies, procedures and systems that can be appropriated to enable collaboration. However, this applies only when there are drivers for collaboration, consisting of interdependency and interest in the project's success. Even in a context not conducive to collaboration, the drivers encourage teams to constitute informal mechanisms, enabling some level of collaboration. A framework for the impact of organizational context on collaboration in international projects is presented.  相似文献   
69.
Existing dynamic programming formulations are utilized for the scheduling of serial linear projects. These formulations cannot, however, be used for the scheduling of nonserial linear projects. The intent of this paper is to present a nonserial dynamic programming formulation for the scheduling of linear projects with multiple non-overlapped loop structures. The objective of the nonserial dynamic programming solution is to provide for the selection of resources, interruptions, and lags for production activities that lead to the minimum project duration. The advantages of this nonserial dynamic programming approach include its ability to handle work interruption and variable production rates. In addition, the developed system produces a graphical representation of the project schedule of minimum duration. A nonserial linear project is treated herein using the proposed method.  相似文献   
70.
The occurrence of an earthquake causes direct and indirect losses in economy. Performance of the built environment can determine both the magnitude of the losses and the speed of recovery from earthquakes. Earthquake losses can be minimized by the use of planning techniques. This paper presents a probabilistic approach for economic evaluation of a shopping center constructed in a seismic zone. Decision-makers can benefit from this approach, before and after an earthquake occurrence, by considering the probability distribution and variability. Life cycle cost concept is taken into account in the formulation of future worth estimation. Therefore, the approach simulates all the benefits and costs, which are prone to variation within Monte Carlo framework. The probabilistic approach can be used to assess the effects of recovery periods.  相似文献   
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