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城市污水管道预报健康度评价模型及其应用研究 总被引:2,自引:1,他引:1
根据现状管道破坏的可能性及其环境影响后果等因素,建立了城市污水管道预报健康度评价指标体系,基于灰色系统理论提出了城市污水管道预报健康度灰色关联综合评价模型,并运用此模型对四川岳池城东新区城市污水管道的预报健康度进行了综合评价.结果表明:运用灰色关联综合评价模型计算得到的预报健康度可为确定污水管道检测的优先次序提供依据,健康度较低的管道应优先被检测;在灰色关联评价法中,将模的大小与夹角的大小结合起来,可以较全面地反映污水管道与虚拟最健康管道的接近程度;采用多时段管道评价矩阵可避免评价模型的奇异性. 相似文献
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在某污水处理厂二期工程两座卵形消化罐的施工中,根据构筑物的建造特点并结合一期工程的施工经验,合理地利用工程桩承担部分侧向土压力,优化了深基坑维护方案,从而大大减少了临时设施工程量,并取得了较大的经济效益. 相似文献
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市政雨污水管道施工质量如何对于城市污水、雨水的正常收集和排放都有重要的影响。只有完善市政雨污水管道的施工工艺,才能够真正意义上确保城市污水和雨水的正常排放。本文结合工程实例,重点分析了市政雨污水管道施工工艺。 相似文献
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城市污水管道是重要的基础设施,对城市生态安全、社会生产发展等都起着至关重要的作用。对某市污水管道的混凝土腐蚀情况进行调查分析,在此基础上开展了室内模拟腐蚀试验研究,提出了污水管道混凝土的耐久性设计方法。研究表明:该城市污水管道混凝土腐蚀破坏的主要因素为硫酸盐侵蚀;采用矿物掺合料、聚丙烯纤维对管道混凝土进行改性,能够有效提高管道混凝土在污水腐蚀环境中的耐久性,双掺粉煤灰和矿渣并添加适量聚丙烯纤维(CX组)的效果最佳,与原配比混凝土相比,CX组混凝土的立方体抗压强度和劈裂抗拉强度分别提高了20. 7%和16. 9%。在试验条件下,水泥基结晶型防水涂料对于管道混凝土耐久性的改善尚不明显。 相似文献
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雨水污水分流解决内河污染--以常德市穿紫河流域为例 总被引:1,自引:0,他引:1
城市内河污染问题在各城市都比较普遍,常德市穿紫河的污染治理是市人民政府作出的一项重大的决策,是解决城市环境污染、造福市民的一项重大工程.要达到治理的目的,需要采取多种手段,除了治标以外,更重要的在于治本,即控制污水的源头,才是最根本的环节,也就是要将城市生产和生活产生的各种污水从它一产生起,就要与雨水分开,直接通过专用污水管道引入城市污水处理厂,而不能混合院内雨水排入雨水系统. 相似文献
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污水管道主要起到排放城市污水作用,是市政道路工程的重要组成部分.污水管道施工效果对市政道路的运行具有直接影响.顶管技术是一项有效的施工技术,在污水管道施工中应用的也较为广泛,可满足污水管道施工要求.为进一步提高顶管技术在污水管道中施工效果,还需以工程实例为主要研究对象,科学、合理地选择和运用顶管技术,保证市政道路污水管道施工质量. 相似文献
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引用了国外桥梁养护加固方法分类标准,总结了国内常用的养护加固决策方法,分析了桥梁养护加固投资决策优化算法的条件及一般的计算流程,介绍了与桥梁养护加固费用密切相关的性能评估与退化的研究概况,以供参考。 相似文献
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为制定科学有效的养护决策,基于高速公路路面性能数据进行神经网络模拟预测了未来 5 个运营年限的路面性能,提出一种新的路面养护决策优化数据包络分析(DEA)模型。该模型以养护里程量、交通量和养护投入资金为输入指标,以路面使用性能恢复值为输出指标,对所提出的 13 种养护方案进行有效性评价,选出投入少、产出高的高效率方案。结果表明:综合考虑交通量、投入资金、产出效率和养护工作量等因素能够客观地筛选出高效率的养护方案。方案结果可为公路管理者做出合理养护决策提供有效依据。 相似文献
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《Structure and Infrastructure Engineering》2013,9(10):783-796
This paper proposes a generalised partially observable Markov decision process (POMDP) combining decision analysis and dynamic programming. The model is applied to a maintenance optimisation problem, even though the scope of its utility is far beyond that particular class of problems and it is relevant to any POMDP. The proposed model allows easy mathematical modelling for optimising complex sequences of decisions that are to be undertaken during each stage. We provide a step-by-step derivation of the mathematical equations for three of the most important types of sequences of decisions to be carried out during each stage of a POMDP and which are used in practice for maintenance optimisation, namely, maintenance action, inspection-maintenance action and inspection-inspection-maintenance action. In a later section, we indicate how to extend the proposed model so that it takes into account epistemic uncertainty that veils the exact value of the probabilistic input parameters of our model. 相似文献
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M. Gunaratne J. L. Chameaut A. G. Altschaefflf 《Civil Engineering and Environmental Systems》2013,30(3):166-170
A methodology for ranking pavement sections according to maintenance urgency has been developed using fuzzy multi-attribute decision-making concepts. First. the pavement sections in a highway network are grouped according to their maintenance needs, using fuzzy pavement serviceability indices. Then, the attributes relevant to each category of maintenance are identified, and an expert knowledge base containing priority values for selected combinations of attribute values is formed in collaboration with decisionmakers. Finally, it is shown how the fuzzy attribute values for each pavement section can interact with the expert knowledge base to produce a unique set of rankings for these sections. This ranking scheme is capable of handling possible fuzziness in the priorities assigned by the decision makers. 相似文献
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利用灰色物元分析法,建立了高速公路路段养护方案的优劣排序模型,对各路段进行多因素综合评价,并结合一具体实例对其进行了分析验证,从而为路面养护决策提供了一种科学的评价方法。 相似文献
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《Structure and Infrastructure Engineering》2013,9(5):655-667
The quantitative assessment of the life-cycle performance of infrastructure systems has seen rapid progress using methods from systems dynamics. Markov chains and Markov decision processes are some of the more useful modelling tools that permit the integration of stochasticity in decisions related to sustainable infrastructure management. In this paper, we explore the effect of uncertainties in the characterisation of these decision models. In particular, we consider the uncertainty in the transition parameters of these models and quantitatively discuss the implication of this kind of uncertainty on the optimal decisions as the solution of these models. We also make the case for the development of rationales that can differentiate between these decision models. In addition, a computationally efficient solution algorithm is introduced for these systems under transition uncertainties. Finally, we demonstrate the sensitivity of the optimal decisions to transition uncertainties and also the computational advantage of the discussed solution algorithm using the problem of optimal maintenance of pavement. 相似文献
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Mehmet Egemen Ozbek Jesus M. de la Garza Konstantinos Triantis 《Construction Management & Economics》2013,31(11):995-1009
While the road maintenance performance measurement systems that are currently in use investigate maintenance level of service (i.e. effectiveness of the road maintenance), the fundamental relationship between the maintenance level of service and the budget requirements (i.e. the efficiency of road maintenance) has not received as much attention. Given that not knowing how ‘efficient’ transportation agencies are in being ‘effective’ can lead to excessive and unrealistic maintenance budget expectations, there is a need for a performance measurement system that can assess the overall efficiency of road maintenance operations. To address this need, a framework was developed and implemented to assess the relative cost efficiency of eight counties in Virginia, USA in maintaining the paved lanes of the Interstate roads. Such framework is developed using a methodology known as data envelopment analysis which is based on the production theory and principles of linear programming. The results indicate that the Rockbridge County is the most efficient and the Roanoke County is the least efficient in maintaining the paved lanes. The findings of this research are intended to be used as guides for benchmarking as well as managerial actions and policy making for decision making with respect to road maintenance. 相似文献
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利用遗传及免疫算法进行桥梁维修管理计划的优化 总被引:2,自引:0,他引:2
以桥梁的耐久性和耐荷性为桥梁的质量指标,建立了考虑桥梁经济性和质量指标的维修加固模型。探讨了简单遗传算法(SGA)和免疫算法(IA)求最优桥梁维修管理计划的解的可能性,并对比了二者解的差别。结果表明当维修计划期间较短时,二者均可给出适当的优化解,当桥梁维修管理计划期间较长时,SGA法得出的准优化解频度减少,解的可靠性降低;而IA法可以给出SGA法无法得出的长期间维修计划的优化解,并给出复数的维修管理计划方案供用户选择。 相似文献