Risk-Cost Optimization of Hydraulic Structures: Methodology and Case Study

Simultaneous consideration of initial construction cost and failure risk in practical design of critical hydraulic structures is a long-standing problem in water resources planning and management. Despite extensive efforts to effectively tackle this problem during recent decades, the traditional rather inefficient technique of return period approach still enjoys being the dominant technique in real-world projects. Accordingly, this article aims at developing an innovative evolutionary-computation-based multi-objective model as a remedy to shortcomings of existing common methods. This simulation-optimization framework generates a series of uniformly distributed trade-off solutions which represent the compromise between competing objectives of construction cost and failure risk. Hydrologic and hydraulic uncertainties along with flood routing process are considered in the optimization process to provide a more complete picture of the problem. This approach is demonstrated and discussed for flood diversion system of Bakhtiari Dam in Iran and the Pareto optimal fronts are found for different combinations of uncertainties. The presented multi-objective approach can effectively enlarge the decision maker’s scope to more efficiently determine the optimum design of the system.     

建筑企业改事势在必行

随着国内经济建设的发展,以及WTO对中国经济影响的与日俱增,建筑业以及相关行业正面临着国内外市场的严峻考验,如何适应新形势的变化,提升企业竞争力,进一步进行建筑企业改革,促进建筑企业的发展壮大,是摆在我们面前亟待解决的重要课题.     

水轮机蜗壳位移原因分析及处理

介绍潘家口防汛自备电站水轮发电机组在试运行中发生的水轮机转轮及主轴密封严重磨损事故的解决方法 .对现场 7次静态充水模拟试验进行分析 ,确认造成转轮及主轴密封磨损的主要原因是机组运行时水轮机蜗壳产生位移所致 .为消除蜗壳位移产生的不良影响 ,采取了水平顶杠支撑、蜗壳地脚基础加固、加大水轮机转动与固定部分运行间隙等综合技术措施 .经此处理后 ,机组恢复正常运行 ,近 3年来未发生类似问题 .     

实施灌区节水改造发挥水利工程效益——以金华市婺城区为例

金华市婺城区通过实施对灌区渠系的防渗衬砌和节水配套改造推广节水灌溉技术等措施,提高了灌溉水的利用系数。使水利工程在节约和充分利用水资源、农业增效和综合生产能力提高、节约人力和能源、促进农村和社会和谐稳定诸方面发挥效益。     

Model Conceptualization Procedure for River (Flood) Hydraulic Computations: Case Study of the Demer River, Belgium

Model-supported real-time flood control requires the development of effective and efficient hydraulic models. As large numbers of iterations are to be executed in optimization procedures, the hydraulic model needs to be computationally efficient. At the same time, it is also required to generate high-accuracy results. Therefore, an identification and calibration procedure was developed for the purpose of having this conceptual model built up and calibrated based on a limited number of simulations with a more detailed full hydrodynamic model. The performance of the conceptual model was evaluated for historical events under different regulation conditions. Robustness test results show close agreement, with Nash-Sutcliffe Efficiency values higher than 0.90. In addition, it is found that the conceptual model is capable of accomplishing simulation of historical flood events within few seconds. That is much faster than the detailed full hydrodynamic model, which enables the conceptual model to be applied for real-time flood control.     

试论水轮机允许吸出高度中的安全系数

水轮机允许吸出高度中安全系数的选用,对机组稳定运行和厂房基础开挖影响较大,是一个复杂的技术经济问题,不能单纯为避免汽蚀而盲目加大安全系数。用经济安全系数的概念,并用模糊数学方法将影响安全系数的众多的定性因素定量化,从而最终选定经济安全系数。通过实例分析对比,证明此法是可行的。     

利用DEM计算河流水力资源理论蕴藏量的实例分析

河流水力资源理论蕴藏量对于河流水力资源合理开发、河流水电规划设计等具有重要的指导意义。河流水力资源蕴藏量主要取决于水量和河道落差,河道落差主要取决于地形资料,一般地形数据通过实际测量或购买已有地形图获得,对于无资料地区或仅开展前期研究,由于DEM易于获取、免费的特点,可以作为地形资料。本次研究以一带一路沿线国家印度尼西亚加里曼丹岛卡扬河为例,基于GIS和DEM进行河流水力资源理论蕴藏的估算。结果显示,卡扬河水力资源理论蕴藏量计算结果基本合理,估算方法简便实用,节省人力物力,为无资料地区河流水力资源理论蕴藏提供了估算方法。     

巨龙舞动金沙江--解读溪洛渡水电站

溪洛渡水电站的正式开工,揭开了金沙江水电开发的序幕。电站建成投产,将成为实施“西电东送”战略的骨干电源,以满足华中、华东地区,并兼顾川渝、滇的用电需要,使“西电东送”有一个较高的起点。同时,它将成为长江防洪体系的重要组成部分,带动金沙江两岸川滇贫困地区的经济发展。     

对水利工程定期审计的初探

1　水利工程建设项目审计的必要性1 .1　法规给予审计部门的权力对水利工程建设项目的审计 ,是审计部门依据国家的财政法规及有关政策、规章、对全社会的财务活动和投资效益审查的内容之一 ,是水利建设项目保障体系 ,是以加强工程建设项目管理 ,提高经济效益为目地的经济监督活动。1 .2　水利工程建设项目性质决定水利工程建设项目 ,投资大、资金流动环节多、涉及部门多、规模大、工期长 ,施工中不确定因素多 ,施工现场分散、条件差、劳动强度大 ,社会共誉性强 ,社会回报率低等特点 ,单一的靠建设单位财务 ,工程技术来对工程进行管理是不够…     

Water Consumption by the Visitor Industry: The Case of Hawaii

The visitor industry plays a pivotal role in Hawaii's economy, accounting for 30% of the gross state product. It is an important consumer of the state's freshwater supply, with a clear potential for substantial additional demand in the years ahead. Water consumption in hotels and golf courses that cater to the needs of the visitor was analysed. Regression analysis showed that size and price were important determinants of water use by golf courses. The numbers of units, swimming pools and golf courses were found to be statistically significant determinants in water consumption by the hotels. Pricing could be an effective instrument in efficient water allocation to golf courses. A small change in price, however, is unlikely to make a major impact on water use decisions by the resorts and hotels.     

水工金属结构的腐蚀与防护措施

文中分析了水工金属结构的腐蚀与环境的关系，腐蚀原因及影响因素，提出了常用的防腐方法、选择原则和防腐措施的质量控制。     

水利工程中基坑支护的施工——以浙东引水萧山枢纽工程为例

以浙东引水萧山枢纽工程为例,就基坑支护在水利工程中的施工作了分析,并就基坑支护技术阐述了经验和体会。     

水力机械中固液两相流研究——水力机械中固液两相流基本方程组

本文建立起了水力机械中固液两相流的基本方程组,对于层流流态,方程组是封闭的;对于湍流流态,方程组是不封闭的,需要相应的湍流模式。导出了旋转相对坐标系上固液两相相互作用力的表达式,与绝对坐标系上的相比,它包含了向心惯性力和科氏惯性力。     

大型水力机组中空化现象的比尺效应

大型水力机组中的空化比尺效应关系到真机的空化性能和水电站装机高程的确定．影响水力机组空化比尺效应的主要因素有：机组运行水头、转轮直径、液体中的空气含量以及流动介质本身的性质等等．本文在前人研究的基础上推导出真机与模型机之间的空化相似率，提出了水力机械模型试验台上空化试验应遵循的相似准则．以岩滩电站为例，根据其模型转轮的空化试验和流场理论分析结果推算了岩滩电站真机的空化特性．建议在确定大型水力机组，尤其是三峡机组的吸出高度时，较多的考虑初生空化系数的影响，取用较接近于真机实际的初生空化系数值，从水电站的设计和机组安装上保证转轮内良好的流态，避免空化引起的破坏．     

计算机算法在求解复杂学公式中的应用

水利工程设计中，经常遇到求解收缩水深he、临界水深hk，和共轭水深h1（或h2）等问题，传统方法采用试算法或图解法，其计算过程复杂、繁琐、工作量大，且精度不高。本通过计算机（BorlandC）编程，建立公式求解的计算机算法模型，可快速准确地推求出数值结果，可供水利设计人员参与。     

复合土工膜在砂质渠道防渗工程中应用的试验研究

0　前言阿城市国营灌区供水干渠总长 85ｋｍ ,其中1 2 35ｋｍ系纯砂质渠道 ,年渗漏水量损失71 88万ｍ3,这对于十年九春旱 ,水资源缺乏的阿城市 ,是一个很严峻的问题。特别是今年春夏连旱 ,水田灌溉用水出现了前所未有的短 ,直接影响农业生产的发展。如何探索最大限度地提高干渠水利用率的有效途径 ,是阿城市水田区抗旱保灌溉夺丰收的必走之路。为探索水田用水砂质干渠提高水利用系数的最优模式 ,我们在民合灌区 30 0 0ｍ砂质干渠段内搞了 30 0ｍ防渗工程 ,采取复合土合膜和混凝土预制板相结合的结构型式 ,并对干渠整个一年供水期进行了水位…     

Analysing the Diversity of Water Pricing Structures: The Case of France

This paper presents the results of a 2003 national survey of urban water pricing structure implemented by 429 district level water utilities. After providing some background elements on the diversity of existing water pricing structures, the paper shows how each structure can be used to achieve different management objectives (water allocation efficiency, costs recovery, and equity). It then describes the structures adopted by French water utilities, showing that flat rate are rarely adopted; declining blocks frequently used; and increasing blocks pricing which should be used to promote water use efficiency remain extremely rare. A statistical clustering is then conducted and a typology of situations elaborated. The paper concludes with highlighting that current pricing structures are influenced by past practices and that the dominant objective of water utilities is to cover costs.     

水利工程质量监督程序

通常人们把对某一水利建设项目的质量监督从办理质量监督手续、施工前监督、施工过程监督、竣工验收监督到质量保修期监督的过程,称为水利工程质量监督程序。可用图1直观表示。具体监督内容如下：     

龙马水电厂水工建筑物安全管理

介绍了龙马水电站大坝运行情况,就大坝监测、水工维护、泄洪闸门运行以及防洪渡汛等方面的安全管理作了叙述和讨论,文中提出的一些管理经验,可供运行和设计部门参考。     

万家寨水电站蜗壳外围混凝土结构的设计与施工

万家寨水电站蜗壳采用全埋式金属蜗壳,设计采用了设置垫层的组合结构,根据组合承载模型计算结果配置钢筋。外围混凝土施工采用分层分块浇筑方案,针对座环下角隅部位不易浇筑密实的情况,设置系统灌浆管进行水泥灌浆。