乌东德水电站泄洪消能设计研究

乌东德水电站泄洪消能建筑物规模大、布置难度高,挖除覆盖层后坝址消能区天然水垫深厚。针对上述特点,对该电站泄洪消能方案进行了比较和研究,选用坝身表、中孔与岸边泄洪洞联合泄洪的方案,坝身布置5个表孔、6个中孔,坝下设置"护岸不护底"水垫塘消能。水垫塘末端设立混凝土重力式二道坝,左岸靠山侧布置3条泄洪洞,并采用封闭抽排水垫塘消能。水工模型试验表明,该方案合理可行,安全可靠。     

构皮滩水电站泄洪消能试验研究

构皮滩水电站坝址河谷狭窄、洪水峰高量大,枢纽最大泄洪功率为42 000 MW,坝身泄洪采用跌流水垫塘消能,岸边泄洪洞采用挑流消能.经水工模型试验方案比选,表孔出口采用平面扩散加齿坎及大差动变值俯角,中孔采用平底型及上挑型相间布置,岸边泄洪洞采用斜切贴角鼻坎,水垫塘底板冲击动水压力在设计标准之内,正常运用期P=20%～0.02%洪水条件下泄洪洞下游基本不冲,较好地解决了坝身泄洪消能和泄洪洞下游消能防冲难题.     

小湾水电站泄洪建筑物布置优化研究

小湾水电站最大泄流量为20700m^3/s，最大水头约225m，泄洪功率高达46000MW。小湾工程河谷窄、坝高、泄量大，经各设计阶段的多方案比选研究，泄洪消能布置采用5个坝顶溢流表孔、6个坝身中孔和左岸一条泄洪洞，坝后设水垫塘和二道坝，坝身设2个放空底孔的泄洪建筑物布置方案。各泄洪消能建筑物在联合泄洪或单独泄洪情况下，既能达到良好的消能效果，又能保证运行安全稳定。     

溪洛渡水电站泄洪洞C9060抗冲耐磨硅粉混凝土施工技术

溪洛渡水电站泄洪消能具有水头高、泄量大、河谷狭窄的特点,泄洪功率近100 000 MW。泄洪消能建筑物由"坝身7个表孔+8个深孔,坝后设水垫塘;左右岸各布置2条有压接无压洞内龙落尾泄洪隧洞"组成。其中泄洪洞长1.3～1.8 km,龙落尾段最大流速为50 m/s,单洞的最高泄流能力为4 162 m3/s。泄洪洞大流量、高流速的特点,必然对混凝土浇筑的施工质量以及温度控制有高标准的要求。溪洛渡水电站左岸泄洪洞龙落尾为C9060抗冲耐磨硅粉混凝土衬砌,在边墙浇筑阶段,通过采取一系列技术质量措施,混凝土的施工质量取得了良好的效果。     

高拱坝非对称泄洪消能布置优化试验研究

白鹤滩水电工程具有窄河谷、大泄量的特点,泄洪消能问题突出.为了避免有限空间内的水舌重叠,采用泄洪表孔3组非对称排布的泄洪消能布置方式.模型试验表明,原布置方案中在坝身泄洪孔口表、深孔单独泄洪时能有效分散水舌,但在坝身表、深孔联合泄洪时,水垫塘内冲击压力峰值超过常规标准,可能影响水垫塘安全运行.通过分析表、深孔水舌的空中...     

高拱坝挑跌流非碰撞水垫塘消能形式研究

在峡谷区修建高坝工程,坝身高水头、大泄量的消能防护是关键技术难题之一。本文通过模型试验和数值模拟,研究了收缩式消能工的作用和分层射流在水垫塘内流动特征与消能机理,论述了坝身分层、多孔、分散泄洪的可能型式及其优缺点。为避免射流水舌碰撞分散引起的溅水雾化问题,通过对坝身表、深孔的不同布置形式,创造性地提出表孔、深孔水舌分层入水非碰撞布局的水垫塘消能方案,和采用收缩式消能工,使表、深孔在横向交错布置,在立面分层泄流,深孔水舌穿过表孔水舌之间的空隙处射出,形成交错入水非碰撞格局的水垫塘消能方案。     

溪洛渡水电站坝身泄洪消能布置

针对溪洛渡水电站具有“窄河谷、高拱坝、巨泄量”的特点，按照“分散泄洪、分区消能”的布置原则，以及“泄小洪水时运行灵活，泄中洪水时充分发挥水库调洪削峰能力，泄大洪水又有足够的超泄能力”的泄量分配原则，开展了多方案的坝身泄洪消能布置比较研究。结合水力模型试验，初步论证了坝身７表孔＋８深孔方案宣泄３００００ｍ＾３／ｓ的可行性。     

高拱坝大流量全坝身孔口泄洪消能布置设计方案研究

本文以叶巴滩工程为例,结合同类工程经验,对泄洪消能布置格局、坝身孔口布置、空中消能方式、水垫塘衬护方式及二道坝设置必要性等方面进行研究和综合比选,推荐采用"全坝身孔口泄洪(坝身布置5个表孔+4个深孔)、坝身分层出流、水舌空中无碰撞、坝后设水垫塘及二道坝"方案,满足工程安全性及经济性要求.     

高水头大流量泄洪消能研究（结合拉西瓦工程部分）

本文是“八五”国家重点科技攻关８５－２０８－０１－０４（结合拉西瓦工程部分）专题研究报告的简述，概括了全部子题的主要研究成果，扼要地论述了拉西瓦水电站泄洪消能布置的优化研究；梯级水库泄洪可靠度及风险分析模式和计算方法的研究；拉西瓦坝身深孔体型优化的研究；拱坝坝身泄洪及水舌冲击水垫塘诱发坝身振动的研究；导流洞改永久泄洪洞及涡流消流工的研究；水垫塘三维紊流场数值模拟计算及消能分析；峡谷区雾化研究等。研     

公伯峡水电站泄洪建筑物布置与设计

公伯峡水电站泄洪建筑物布置采用了两岸分散、左岸相对集中的平面布置格局，立面上采用表、深孔相结合的分层孔口布置，设置了开敞式岸边溢洪道、深式压力泄洪洞以及采用开敞式进水口的水平旋流泄洪洞。泄洪建筑物布置格局合理、型式多样、运用灵活，妥善解决了泄洪建筑物泄洪、排沙、放空、检修、施工期放水等运用要求。同时水平旋流消能泄洪洞在国内的首次应用，丰富了泄洪建筑物的型式，为导流洞的永久利用提供了新的经验。     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

浅谈天湖水电站水轮机运行故障及处理措施

简述天湖水电站投运以来各种故障的表现形式，分析其原因，提出了相应的处理方法及措施，并对合理利用国内外设备提出建议。