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传统的高桩码头靠船构件多采用悬臂板式或悬臂梁式,这种构件能沿码头长度方向全面保护,但材料用量多,造价高,主要适用于水位差5米以下的地区。当水位差继续增大,这两种靠船构件就不适用了。本文综述了靠船桩式、多层固定系靠式(框架式)、浮式以及浮码头等几种适用于大水位差地区码头的靠船构件的结构型式,对这几种靠船构件的结构特点、功能原理、适用条件、优缺点等进行了对比和分析。 相似文献
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林金裕 《水利水电科技进展》2020,40(6):54-59
为了给闽江航道整治、码头建设、防洪、船闸设计提供技术参数,在外业资料缺乏情况下,采用数值模拟、外业观测、相关分析相结合的方法计算闽江水口水电站下游航道设计最低通航水位。基于非结构网格、有限体积法建立闽江干流水口水电站至马尾河段的二维水动力数学模型,通过数学模型推算闽江水口水电站下游航道沿程临时站点逐时水位,将沿程临时站点逐时水位与竹岐站、文山里站、白岩滩站等长期水文站(基准站)水位建立相关关系,采用累积频率法计算低潮累积频率90%的水位特征值作为基准站设计最低通航水位,通过该相关关系计算沿程临时站设计最低通航水位。计算结果表明,临时站逐时水位与基准站逐时水位线性相关关系较好,相关系数基本在0.9以上,由该相关关系及基准站设计最低通航水位获得的闽江干流水口水电站下游航道设计最低通航水位值相对合理可靠。 相似文献
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输电线路工程跨越通航河流,需办理“架空电缆(线)工程建设方案行政许可”,该行政许可主要技术内容是水文设计,其中涉及的最高通航水位直接影响到航道通航安全,也是行政部门审核的关键,因此设计过程中资料收集、设计洪水位计算、航道等级及最高通航水位的确定尤为重要.笔者以糯扎渡送电广东±800 kV直流输电线路工程跨越北流河为例,介绍了输电线路工程跨越通航河流水文设计的相关工作. 相似文献
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区别于一般的水面漂浮式光伏,通航库区漂浮式光伏由于其特殊的环境条件和额外的通航设计要求,需要进行针对性的系泊系统方案设计。基于库区通航河道水体深、水位变化大、流速大、河面宽以及通航需求等特点,计算漂浮阵列所受载荷,进行阵列及系泊系统一体化耦合分析,根据系泊载荷,不同水位变化和航运等级进行系泊线规格、长度及数量、系泊线配重块规格及数量、桩锚规格及数量以及布置方案的设计,并通过计算分析验证了系泊系统方案满足设计要求。 相似文献
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结合淮柴闸枢纽工程设计,建立水流三维数学模型,基于CFD数值模拟技术,采用vof两相流与雷诺时均Realizableκ-ε模型,分析了该枢纽水流流动特性。结果表明,在设计水位工况下,其最大横向流速远超过GB50139-2014《内河通航标准》规定的0.3m/s,不满足通航要求;当该闸通航来流流速不超过0.1m/s,最大过闸流量不超过5.5m~3/s时,通航安全能得到保证。采用CFD数值模拟技术模拟水闸及通航建筑物水流运动过程是可行的,可对类似工程优化布局和设计提供一定借鉴和参考。 相似文献
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考虑水位过程变异的非一致性最低通航水位设计方法 总被引:1,自引:0,他引:1
在河道断面水位年际变异和年内分配变异的综合作用下,基于历史资料的最低通航水位设计值已无法反映真实的水位变化规律,导致船舶的通航安全面临威胁。为设计出合理的最低通航水位,本文结合分解合成思想和二阶矩变异概念,提出了考虑水位过程变异(即不同时间尺度下水位特征值的年际变异和水位过程的年内分配变异)的非一致性最低通航水位设计方法——频率-保证率法。该方法不仅符合工程水文学中关于设计水文过程的定义,兼顾了年保证率和频率的概念,而且综合考虑了水位年际和年内分配的双重变异,可为其它工程水文设计提供参考。本文将该设计方法应用于澜沧江允景洪水文站,并将设计结果与均值变异条件下采用频率-保证率法、方差变异条件下采用综合历时曲线法的设计结果作比较,对本方法的优势进行了验证和讨论。 相似文献
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河岸码头建筑物势必导致其上游水位壅高及对码头附近水流流态产生影响。以汉江沙洋河段为对象,通过定床概化物理模型试验研究了码头建筑物对河道水位与流速场的影响。并基于能量平衡原理,采用河道恒定非均匀流水面曲线基本方程,结合物理模型试验资料,计算了码头建筑物附近的水位变化值,并提出了码头建筑物产生的水位壅高值的计算方法。 相似文献
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生态浮床是一种应用广泛的水质净化水体修复技术。在河道中布设生态浮床会干扰水流结构,影响河道行洪排涝能力。本文区分低透水性浮床主体区和高透水性浮床根系区,运用两层式固定多孔介质域概化生态浮床,构建生态浮床不同布设方式的水槽三维水动力数学模型,对比分析无浮床、浮床不同间距串联或交错排列等14种工况的水槽水动力特性及其变化规律。布设浮床后浮床上游水面壅高、下游水面先局部降低后恢复,浮床段流速垂线分布呈“纺锤形”且平均流速和紊动能明显增大。相较于串联排列,交错排列方式对水流结构影响程度较大,且水位、流速、紊动能等水动力参数随浮床间距的变化趋势相异。因此,考虑对洪水位的壅高及增强水流紊动强度利于污染物扩散,实际应用中需结合研究成果合理选择生态浮床的布设方式。 相似文献
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A. V. Aleksandrov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(6):342-347
A ferroconcrete drilling platform is a floating structure built in a dry dock and then transported by towboats to the place
of its installation on the shelf.
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Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 10, October 2006, pp. 19–25. 相似文献
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Lowland rivers impounded by weirs are often operated to provide stable water levels. In the lower River Murray, stable water levels promote algal biofilms dominated by stalked diatoms, filamentous green algae and Cyanobacteria. In summer 2005–2006, the Lock 5 weir pool was surcharged for environmental benefit. Algal biofilms grown on artificial substrates were compared to the following year when the water level remained stable. On both occasions, substrates were fixed at 300‐mm depth in the river channel and a connected wetland. During the surcharge, additional floating substrates were deployed to control for the change in water level. The algal communities that developed during both years were dominated by diatoms. A greater diversity in the biofilm community was evident during the 4‐month surcharge when compared with the following year. This was due to a much greater change in algal biofilm community composition over the 4 months of the surcharge, compared with biofilms grown during a period of stable water level, when the community changed little after 1 month. The lack of difference between fixed and floating substrates suggests that the change in water level was not responsible for the difference between the surcharge and stable level biofilms. Possible reasons for the difference between years include light, nutrients and water temperature. Although the effect of the surcharge could not be definitively defined, these results provide some evidence that weir pool surcharge may be used to improve algal biofilm diversity when compared with the current stable water level regime. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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The artificial ecological floating bed is widely used in rivers and lakes to repair and purify polluted water. However, the water flow pattern and the water level distribution are significantly changed by the floating beds, and the influence on the water flow is different from that of aquatic plants. In this paper, based on the continuous porous media model, a moveable two-layer combination model is built to describe the floating bed. The influences of the floating beds on the water flow characteristics are studied by numerical simulations and experiments using an experimental water channel. The variations of the water level distribution are discussed under conditions of different flow velocities( v= 0.1 m/s, 0.2 m/s, 0.30 m/s, 0.4 m/s), floating bed coverage rates(20%, 40%, 60%) and arrangement positions away from the channel wall( D= 0 m, 0.1 m, 0.2 m). The results indicate that the flow velocity increases under the floating beds, and the water level rises significantly under high flow velocity conditions in the upstream region and the floating bed region. In addition, the average rising water level value(ARWLV) increases significantly with the increase of the floating bed coverage rate, and the arrangement position of floating beds in the river can also greatly influence the water level distribution under a high-flow velocity condition(v ?0.2 m /s). 相似文献
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在分析长江涪陵段的水沙特性和三峡水库蓄水前后该河段河床演变趋势的基础上,运用二维水流数学模型,分析了4种流量组合情况下在三峡水库运用前和运用50年,涪陵港区码头修建前后的水位、流速变化及其影响范围.结果表明,修建涪陵港区码头对该河段的防洪及河势变化影响不大. 相似文献
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为改善水利工程现有治漂措施存在功能相互独立、操作被动、效率低等不足,保障工程效益和水面安全,依据漂浮物特性、河势及工程布置特点,利用水力一体治漂浮排、浮槽、浮闸进行水力学模型试验,对水力一体拦、导、清(排)漂治理技术进行研究,多方案组合试验均取得因势利导一体化综合治漂效果。其中,主要技术"水力一体治漂浮排"经工程现场实际运用检验可实现主动、大量治漂,可拦截各类大型危险漂浮物,减少中间操作环节。研究结果表明,水力一体化治漂方式能够适应漂浮物特点,改善治漂方式,可以为工程长效稳定治漂提供技术支撑,其实用装备可应用于各类相关工程,为水利枢纽构建水面安防系统提供技术支持。 相似文献