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本文主要叙述如何利用现代高新电子技术,研制新型的水文缆道综合测验控制设备以及在缆道绞车控制、起点距入水深测量和流速测量等设备方面的新设计;重点讨论了如何在大中型河道上利用自动或半自动水文缆道测流来实现安全快速的流量测定,支持洪水预警系统中的预报速度和精度,将洪水灾害减至最小。 相似文献
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阿勒腾努尔·温尼尔汗 《水利科技与经济》2013,19(8)
分析了水文缆道与船测测流现状、测量过程中存在的误差估算、误差类型,分别论述了各类误差的引起原因及控制措施.为减少水文缆道与船测测流过程中的测流误差保证测量精度,提出误差控制措施,并建议在测垂线水深子程序过程中引入二次入水操作. 相似文献
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水文缆道是水文测站进行江河流量测验等工作的主要设备,铅鱼则是悬索缆道悬吊流速仪的基本器具。铅鱼的作用在于借助自身的重量克服水流冲击力,使缆道悬吊的流速仪能够垂直下放至预定位置,并稳定和较准确地进行水深、流速测量。若铅鱼轻,则悬索偏角大,影响测验精度;若铅鱼太重,则须考虑缆道设备的结构强度、动力功耗及悬吊系统的荷载能力。在部标准SD121-84《水文缆道测验规范》(以下简称“缆道规范”)中,对不拉偏缆道铅鱼重量G的选择只规定了下限,即窄深河道(深宽比大于1/100)取G 相似文献
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根据水文缆道受风浪影响自古以来水面信号失真的原因,改进水面信号设施,采用静水器施测水面信号,对缆道水深测量和流速仪测点深准确放置,消除风流影响的误差,具有重要意义。 相似文献
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超声波测深技术在溪洛渡枢纽水文监测中的应用 总被引:1,自引:0,他引:1
水深测验的精度直接影响到流量测验的准确性。基于超声波测深技术研制出HSH-IL型测深仪,它可采用缆道钢绳和水体作为测量信号传输通道,不需要专门导线;同时采用信号迭加概率分析技术,提高超声波测深精度和可靠性。在金沙江溪洛渡水电站截流施工中,根据水深流急、施工干扰突出的特点,在相应水文监测断面上布设HSH-IL型测深仪施测,满足了流量测验的可靠性和时效性要求,取得了较好的效果。 相似文献
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水文缆道维修与保养方法探讨 总被引:1,自引:0,他引:1
水文缆道是我国基层水文测站进行河道流量、泥沙测验的一项专用基本设备,特别是在中小河流上的水文测站,基本上都采用水文缆道进行流量测验、沙量取样工作,所以,对于水文缆道的维修和保养,是水文测站人员必须面对的日常性工作,水文测站人员既要熟悉水文缆道的结构、工作原理及操作方式,也要熟悉水文缆道的维修及保养程序。 相似文献
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近几年来,新疆伊犁水文水资源勘测局先后引进6台EKL型水文缆道设备,并分别应用于不同特性的河流,选择沙质河床和卵石河床组成断面的四个水文站进行测深、测宽及流量比测试验,通过对EKL设备的测深、测宽功能及流量实测资料进行统计分析计算,分析了该设备在沙质河床和卵石河床河流上的应用。通过分析得出:河床组成和河床质的分布对测深的影响较大,河床质粒和分布不同,对断面面积测验的影响不同,测宽误差对流量测验精度的影响不大。 相似文献
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文中叙述了义棠水文站淤泥质河床上缆道测流信号的形成、传输、处理系统的设计、试验研究的基本情况及工作原理等。“失重”开关与河底开关组成的双重保险装置是解决我国北方地区淤泥质河床水面、河底、流速信号的产生与传输的自动化缆道的关键问题,文中对之做了具体叙述,旨在为类似的水文缆道工程设计提供参考。 相似文献
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悬索缆道铅鱼重量的选定,由于影响的因素较多,目前还没有比较理想的计算方法,文中通过对影响铅鱼重量的水力条件因素和缆道参数条件等控制性因素的分析,提出了开口式悬索缆道在拉偏状态下铅鱼重量的计算方法,用以在悬索缆道铅鱼重量设计中,合理选定铅鱼的重量,保证缆道测流的精度要求和设施设备的正常运行。 相似文献
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水库下游悬移质泥沙沿程恢复是河流泥沙动力学研究的难点问题之一。对该问题的研究有助于推动学科发展,解决工程实践中的有关问题。针对此现状,归纳总结了平衡及不平衡输沙条件下悬移质浓度垂线分布、悬移质沿程恢复的天然河道实测资料分析和恢复饱和系数等方面的研究成果,认为在不平衡输沙条件下悬移质泥沙垂线分布研究及实测数据的获取、分析等方面还存在一定的不足。在此基础上,提出有必要进一步开展水库下游悬移质泥沙沿程恢复研究,特别是利用精准的测量仪器,开展科学合理、系统全面的水槽试验是丰富该研究成果的必要手段。 相似文献
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2000年,在沱江富顺水文站的缆道建设中,按照水利电力部《水文缆道测验规范》(SD121-84)和中华人民共和国《河流流量测验规范》(GB50179-93)的要求,根据“安全、准确、经济”的原则,针对站址位于富顺县城居民区的特点,设计出变频无级调速平衡式缆道系统,并采用了其它行业中的新技术新产品:YEJ电磁制动交流电机、摆线针轮减速机、MC铸型尼龙滑轮。自2001年1月正式投入水文资料的观测到现在,富顺水文站缆道系统运行良好,350kg采样器的提、放、出、回均能按设计要求完成,系统工作噪音小,运行平稳,在不使用电动运行情况下,手工摇测也能完成测量任务,测量信号达到规定的要求。 相似文献
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When subway tunnels are routed underneath rivers, riverbed scour may expose the structure, with potentially severe consequences. Thus, it is important to identify the maximum scour depth to ensure that the designed buried depth is adequate. There are a range of methods that may be applied to this problem, including the fluvial process analysis method, geological structure analysis method, scour formula method, scour model experiment method, and numerical simulation method. However, the application ranges and forecasting precision of these methods vary considerably. In order to quantitatively analyze the characteristics of the different methods, a subway tunnel passing underneath a river was selected, and the aforementioned five methods were used to forecast the maximum scour depth. The fluvial process analysis method was used to characterize the river regime and evolution trend, which were the baseline for examination of the scour depth of the riverbed. The results obtained from the scour model experiment and the numerical simulation methods are reliable; these two methods are suitable for application to tunnel projects passing underneath rivers. The scour formula method was less accurate than the scour model experiment method; it is suitable for application to lower risk projects such as pipelines. The results of the geological structure analysis had low precision; the method is suitable for use as a secondary method to assist other research methods. To forecast the maximum scour depth of the riverbed above the subway tunnel, a combination of methods is suggested, and the appropriate analysis method should be chosen with respect to the local conditions. 相似文献
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溪古水电站架空索道的设计与应用 总被引:3,自引:0,他引:3
架空索道在水电工程施工中经常使用.它解决了高陡边坡材料运输的实际难题.通过溪古水电站成功应用架空索道的实例,具体介绍了架空索道简便而实用的设计计算过程及施工方法,可供类似工程借鉴与参考. 相似文献
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Md Aynul Kabir Dushmanta Dutta Sadayuki Hironaka Alexis Pang 《Water Resources Management》2012,26(5):1143-1163
Bed load transport is a key process in maintaining the dynamically stable channel geometry for restoring the form and function
of river ecosystems. Bed load consists of relatively large sediment particles that are moved along the streambed by rolling,
sliding or saltation. Currently, various empirical correlations are used to estimate bed load transport rates since no single
procedure, whether theoretical or empirical, has yet to be universally accepted as completely satisfactory in this aspect.
Bed load particles are primarily sourced from river bed materials or banks. The amount of bed load and its spatial distribution
contributes significantly to river bed level changes. Hillslope sediment contribution, mostly available to the river in the
form of suspended load, also plays an important role in river bed level changes. This study aims to analyse different bed
load equations and the resultant computations of river bed level variations using a process-based sediment dynamic model.
Analyses have revealed that different bed load equations were mainly deduced from the concept of relating bed shear stresses
to their critical values which are highly factored by the slope gradient, water discharge and particle sizes. In this study,
river bed level variations are calculated by estimating total surplus or deficit sediment loads (suspended loads and bed loads)
in a channel section. This paper describes the application of different widely used bed load equations, and evaluation of
their various parameters and relative performances for a case study area (Abukuma River Basin, Japan) using a basin-scale
process-based modelling approach. Relative performances of river bed level simulations obtained by using different bed load
equations are also presented. This paper elaborates on the modelling approaches for river bed load and bed level simulations.
Although verifications were not done due to unavailability of field data for bed load, qualitative evaluations were conducted
vis-à-vis field data on flow and suspended sediment loads as well as the bed loads presented in different past studies. 相似文献
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受黎河河道两岸铁矿砂影响,引滦输水黎河段水体中悬浮物含量远远高于引滦入津隧洞出口水的悬浮物含量。本文对引滦输水过程中悬浮物的沉降迁移特征进行了研究。结果表明:影响水体中悬浮物沉降速率的主要因素为悬浮颗粒粒径,影响悬浮物迁移量的主要因素为悬浮物的初始浓度。结合引滦输水过程中的悬浮物实际迁移情况,得出悬浮物主要影响引滦输水黎河河道,而汇入于桥水库的悬浮物含量较少且主要为粒径10μm的颗粒。应用研究成果,针对引滦输水工程的悬浮物污染特征,提出降低输水过程流速、增加入库前河道深度及种植水生植物等建议,以减少引滦输水过程中悬浮物含量。 相似文献