旬河柴坪水电工程综合开发效益分析

水电是可再生的清洁能源,符合目前全球节能减排和低碳生活的发展要求,值得大力发展。本文针对旬河干流镇安段水能资源状况,提出建设柴坪水电工程的方案,并对综合开发前景进行了论证分析,供水利水电技术人员参考。     

黄家湾水电站工程水库规模及装机规模的优化设计

黄家湾水电站是旬河流域镇安段梯级开发方案中的龙头电站,水库规模及装机规模的设计、选取至关重要,通过设定多种方案,从电量效益、淹没指标、工程投资和经济指标等进行综合比较,分析确定黄家湾电站正常蓄水位、死水位、装机容量及额定水头。对黄家湾水电站的最佳运行提供了依据。     

镇安抽水蓄能电站水文设计

镇安抽水蓄能电站位于陕西省商洛市旬河的支流月河流域内,月河流域无实测水文资料。上水库属于特小流域,下水库属于小流域,上、下水库高差达到447 m。针对上、下水库的特点及可依据的资料,采用多种方法推求两个水库的径流、洪水和蒸发量,结合抽水蓄能电站特点,进行成果的合理性分析,提出推荐采用的水文成果。     

旬河流域年径流的突变分析

为研究在气候变化与人类活动双重影响下旬河年径流的突变特性,采用滑动平均法和滑动t检验分别分析旬河年径流的趋势和突变点,再结合旬河流域已有的降水变化规律分析径流突变的驱动因素。结果认为:旬河流域1956~2011年径流量存在"平缓下降—剧烈下降—急剧上升"的变化趋势;下降突变点发生在1975年,上升突变点发生在2002年,均通过显著性检验。进一步结合流域已有降水量规律得出结论:旬河流域降水量的变化是其年径流的趋势变化与突变点产生的主因。     

青山嘴水库工程创新移民安置方式效果和问题分析

水利工程移民安置,实行以"城镇安置化"和"城市宗地安置"的安置方式是云南移民安置的创新,是解决我国西部(云南、四川、西藏、贵州等地)地区水电发展与工程建设占地移民安置矛盾较为可行的一种安置方式、为当地移民群众乐于接受的安置方式。     

旬河干流水能梯级开发规划环境影响评价优化调整建议

根据旬河流域环境现状调查结果,对旬河干流水能梯级开发规划从发展定位、环境布局、开发规模、开发时序等方面进行合理性分析。提出优化调整建议为:将规划的23级水电站中2个梯级取消建设,3个梯级调整开发方式,7个梯级降低开发规模;旬河支流不再进行水电开发,干流各级水电站将多年平均流量的10~30%作为生态流量在坝址处下泄;流域统筹实施鱼类增殖放流;开展环境影响跟踪评价。     

旬河流域出口断面洪水预报方案研究

旬河作为安康水库～蜀河坝址之间汉江最大一级支流，占区间流域面积的48．93％。旬河流域山高林密、植被良好，雨量充沛，近年来洪水频繁，且峰高量大，研究其出口断面洪水预报方案，建立洪水预报模型，对保障蜀河水电站防洪度汛及下游人民生命财产安全起着十分重要的作用。     

商洛市“丹治”工程成效与启示

<正>商洛市位于陕西省东南部,秦岭南麓,鄂豫两省交界,总面积1.93万km~2。境内沟壑纵横,河流密布,共有大小河流及其支流7.25万多条,分属长江、黄河两个流域,其中长江流域1.67万km~2,占全市总面积的85%,主要河流有丹江、洛河、金钱河、乾佑河和旬河,年均降水量710~930 mm。商洛地貌结构复杂,是一个"八山一水一分田"的土石山区。自然条件客观上决定了商洛是水土流失易发区。     

开发月河梯级水力资源促进镇安经济全面发展

月河地处镇安县西部地区,是旬河流域在镇安县境内的最大一级支流.该流域总面积为563km2.年降水量在1000mm左右.流域内有杨泗乡和月河乡两个乡,六个村民小组,1180户4450人.该流域内水力资源十分丰富.规划梯级开发水电站11座,总装机2.370万kW,占全县规划开发装机19.29万kW的12.29%.到2006年,已建成发电6座,总装机1.01万kW,占该流域规划开发总装机的42.62%.     

浅议旬河流域水电站建设对生态环境的影响及保护

详细介绍旬河流域梯级水电站建设对生态环境的影响,提出了相关的保护措施,在这些措施的保护下,该流域水电站的建设必将取得很好的社会效益和经济效益.     

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。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

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。     

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。     

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.