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决定水库蓄水位高低的因素主要有工程环境、水库最高蓄水位、最低蓄水位、水库下游蓄水量及工程投资和淹没损失等,文章通过对关坝水库水位选择进行探讨,从充分利用水资源方面考虑,随着水库正常蓄水位的增加,水位为817-829m时水库供水量的增加与水位关系基本为线性增加关系,正常蓄水位越高供水量越大。从淹没损失方面考虑,由于825m高程以上分布有村寨,水位抬高后将导致淹没投资大幅增加,最终选择关坝正常蓄水位为823m。 相似文献
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正常蓄水位是水库和水电站最重要的设计参数之一,是确定拦河坝高度、水库容积、利用水头和发电能力的基本依据;对水工建筑物的工程量、水库调节性能和水头的利用关系极大,对水库和水电站的建设工期、投资、动能经济效益以及水库淹没损失等均有重要影响。文章以花甲水库工程挡水坝的正常蓄水位选择为例,从水库供水量、水库淹没、工程投资对水库正常蓄水位的影响等方面做简要分析论证。 相似文献
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通过对两个正常蓄水位方案发电量、投资、水库淹没指标等的分析,并对方案进行经济比较,综合分析确定珊溪水库正常蓄水位。 相似文献
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已建坝正常蓄水位调整是挖掘水库兴利能力的有效途径,但目前缺乏明确可靠的论证方法。采用水文学、大坝安全、大坝风险及生态环境理论,研究已建坝正常蓄水位调整必要性的影响因素及特征,分析调整后水库防洪安全、工程安全、库区淹没、库岸结构、库区水环境所受影响特征,提出了正常蓄水位调整必要性论证的6个一级、14个二级指标体系,以及调整后影响论证的7个一级、23个二级指标体系及其分析方法,构建调整方案风险效益分析方法,并应用于杭州青山水库正常蓄水位调整论证。结果表明:针对青山水库将正常蓄水位提高2.0 m的推荐方案,提出的论证指标体系和论证方法合理有效。 相似文献
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<正>常蓄水位选择是水电站设计工作的一项重要任务。本文以胜利水电站为例,分别从梯级电站水位衔接、水能资源利用、水库淹没和工程经济评价四个方面出发,阐述了水电站拦河坝正常蓄水位的选择过程,分析了影响正常蓄水位的制约因素,并通过合理比选,最终确定了胜利水电站的正常蓄水位方案。 相似文献
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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。 相似文献
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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. 相似文献
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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. 相似文献
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V. K. Konovalov O. V. Yashkin V. V. Ermakov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2008,42(2):105-109
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.
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Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008). 相似文献
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Peter B. Bayley 《河流研究与利用》1991,6(2):75-86
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. 相似文献
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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。 相似文献