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61.
该文针对目前高速公路工程试验检测管理工程的现状进行分析,然后以某高速公路工程为例,详细分析如何做好高速公路工程试验检测管理工作。 相似文献
62.
A survey of construction companies' secondary disability management practices was undertaken in the state of Victoria, Australia. The results indicate that formal rehabilitation and return‐to‐work programmes and practices are not adopted in many companies. Smaller construction firms were less likely to have adopted formal programmes or practices than medium‐to‐large firms. In particular, construction companies reported difficulties in the provision of suitable alternate or light duties for workers returning to work following an injury. Most companies regarded disability management practices to have increased operating costs while yielding little or no benefit in terms of reducing lost workdays. Strategies to overcome some of these impediments to rehabilitation and return‐to‐work in construction are recommended. 相似文献
63.
64.
John Kelly 《Construction Management & Economics》2013,31(4):435-442
Value management is a project‐focused process that makes explicit and appraises the functional benefits of a product, process or service consistent with a value system determined by the client. The value system of the client necessarily requires a method for value setting using harder performance variables than the commonly described facets of time, cost and quality. Current value theory is critically appraised in the context of current value management practice. The research proposition is that the constituent parts of time, cost and quality can be made overt enabling a client to express satisfaction in terms of a finite number of variables enabling the explicit statement of client value within a value management workshop. An action research study into the discovery of the component parts of the client's value system at the early stages of construction projects concludes that the variables are the nine non‐correlated, high order, discretionary performance variables of capital expenditure, operational expenditure, time, esteem, environment, exchange, politics/community, flexibility and comfort. 相似文献
65.
The construction industry is based on craftsmanship. Quality control and assurance procedures applied in manufacturing cannot usually be readily applied in construction, where there are higher degrees of uniqueness in each project. One category of companies, industrialized housebuilders, is attempting to bridge some of the gaps between construction and manufacturing. These companies prefabricate building modules for later assembly at the building site. Since they are wholly responsible for large parts of the building process, these companies have greater opportunities to control and improve quality in a more consistent way than ordinary construction companies. Thus, it could be hypothesized that the frequency and severity of defects should be lower in industrialized housing than in ordinary construction. The aim of the study presented here is to examine this hypothesis by measuring and characterizing defects in industrialized housing. The design and manufacturing processes at two Swedish timber module prefabrication firms has been analysed through interviews, site visits and document reviews. Quality audits from three phases of the building process were compiled, analysed and categorized to provide statistical measures of defects in industrialized housing. The results show that the case study companies are better in terms of product quality than conventional housing. 相似文献
66.
Jeff R. Wright Steven C. Egly Hugh W. Gallivan 《Civil Engineering and Environmental Systems》2013,30(1):16-21
The focus of this research was the development of a model to address the problem of reassigning summer construction workers to winter snow and ice removal teams in an efficient and cost-effective manner. The model is a multi-objective integer program that can generate the complete and precise trade-off curve between the objectives of minimizing total distance that the reassigned workforce must travel from their respective homes to one of many site locations, and minimizing the maximum distance that any one worker must travel. System constraints include demand requirements for workers at each site and the limited availability of state-owned vehicles that may be issued to workers assigned to remote sites. Details of the model structure and solution procedure are presented together with the results of an actual application. 相似文献
67.
68.
《Structure and Infrastructure Engineering》2013,9(3):389-401
In the existing infrastructure management systems, optimal interventions strategies (OISs) are determined for objects that deteriorate gradually (manifest deterioration process, MDPs), under the assumption that with appropriate inspection and intervention strategies the probability of failure of object can be neglected. Objects that deteriorate suddenly (latent deterioration process, LDPs), for example, due to scouring during a flood or earth movements during an earthquake are not considered. The determination of OISs for an object that deteriorates due to both MDPs and LDPs requires the consideration of both. The latter, however, means that the probability of failure of the object must be considered. In this article, a Markov model is presented that can be used to determine OISs for multiple objects of multiple types affected by uncorrelated MDPs and LDPs. The model is an extension of the model proposed by Mayet and Madanat (Incorporation of seismic considerations in bridge management systems. Computer-Aided Civil and Infrastructure Engineering, 17:185–193, 2002). In the model, a set of condition states (CSs) is used to describe the condition of objects of each type, where each set is composed of non-failure CSs and failure CSs. The probabilities of going from each non-failure CS to each failure CS are estimated using normalised fragility curves, and the probabilities of going from each non-failure CS to each non-failure CS are initially estimated using the Markov deterioration prediction model of Kobayashi, Kaito, and Lethanh (A Bayesian estimation method to improve deterioration prediction for infrastructure system with Markov chain model. International Journal of Architecture, Engineering and Construction, 1:1–13, 2012a) and later adjusted taking into consideration the probabilities of entering the failure CSs. The use of the model is demonstrated using a road link comprising one road section and one bridge. 相似文献
69.
Richard K. Morgan Roger Bowden 《The International journal of environmental studies》2013,70(2-3):161-167
In recent years there has been a move in New Zealand to convert small, uneconomic orchards to other agricultural uses. Overseas research has demonstrated that copper from fungicide sprays often accumulates in the soils of orchards and can cause certain problems for plant growth and livestock. To date, no assessments appear to have been made of the degree of copper accumulation in such older orchards in New Zealand. This study presents the results of an assessment of two well‐established apricot orchards in the Central Otago region of South Island, New Zealand. Two aspects of the results are surprising. The first is the relatively low levels of copper in the soil when compared with results from another orchard in the region. That orchard is 18 years old and mean soil copper has already reached 100.0 μg/g, indicating a much faster rate of accumulation than in the two orchards in the current study. The second unexpected result is that the younger orchard has a significantly higher level of copper than the older orchard. Reasons for these findings are discussed in relation to apparent differences in soil properties. 相似文献
70.
交通安全工作直接关系到职工的生命和企业财产安全,关系到企业的稳定和经济建设的发展。本文探讨了抓好交通车辆管理的途径,并对筑牢交通安全堤防展开探讨。 相似文献