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1.
老木孔航电枢纽是岷江干流下游乐山—宜宾162 km河段近期开发4个航电梯级中的第1级,其施工期的通航条件将直接关系到岷江乐山—宜宾段大件船舶运输。为保障施工期岷江航道畅通,施工一期采用左岸扩挖明渠临时航道通航。采用水工物理模型试验与船模试验相结合的研究方法,对施工一期第1个枯水期三江村左汊通航期枢纽坝区通航方案及通航水流条件进行系统研究,提出左岸扩挖明渠疏浚、明渠进口段布置、明渠下游出口及连接段布置推荐方案,以及相应的通航水流条件特征参数。结果表明:老木孔枢纽施工期坝区推荐布置方案通航水流条件良好,获得的最小和最大通航流量满足施工期通航要求。  相似文献   

2.
岷江龙溪口航电枢纽是一座以航运为主、航电结合的大(2)型综合利用水利枢纽工程。该工程施工期通航条件的好坏,将直接关系到岷江乐山至宜宾段航道能否满足大件船舶安全畅通的运输要求,意义重大。根据龙溪口航电枢纽工程施工导流模型试验成果,分析了各施工导流期的通航水流条件,并针对施工通航存在的问题特别是二、三期围堰区段流速超标、流态较差、通航流量较低等相关问题,提出了改善施工期通航水流条件、提高通航流量的综合性工程措施,较好地解决了本枢纽工程施工期的通航问题,其研究成果可作为类似工程借鉴和参考。  相似文献   

3.
为了保证利泽航运枢纽修建阶段航道能够保证基本的安全通航功能,根据利泽航运枢纽工程施工导截流1:100正态定床物理模型试验的成果,从流速、流态、通航流量以及航行路线等角度分析施工导流期三期的通航水流条件以及围堰截流试验情况,并得出截流时不同龙口宽度的计算参数。结果表明,提出的施工三期导流围堰方案所得出的试验结果在流速、流态等水流条件方面均可较好地解决本枢纽工程的施工期通航问题。  相似文献   

4.
湘江株洲枢纽工程施工期通航水流条件试验研究   总被引:1,自引:1,他引:0  
根据株洲航电枢纽工程施工导流模型试验结果,分析一期施工期间利用右汊河道泄流及通航的水流条件。分析表明,施工期右汊河道进、出口段在枯水期均出浅碍航;汛期右汊进口段具有明显的急流滩险特点,流量大于3600m^3/s时,船舶航行困难。针对施工期通航水流条件,提出改善施工期通航条件的一些措施。  相似文献   

5.
黄春华  刘霞  马茂原 《水运工程》2023,(11):137-142
大藤峡水利工程施工量大、建设周期长,必须采取措施保障枢纽施工期航道通行安全。针对一期施工导流围堰布置方案建立物理模型,研究该工程措施下明渠通航水流条件及可能造成安全隐患的因素。结果表明:纵向围堰上游头部处挑流引起结构腰部产生缓流区,明渠水体顺流束窄,不利于施工期船舶通航。在削除主槽局部凸滩、头部增设临时导流墙后导流明渠内水流流态明显改善。最大通航流量条件下各测点流速值均小于5.00 m/s;在下泄流量小于1.20万m3/s时,各测点流速值均小于3.00 m/s,满足自航通行要求。导流明渠沿程水面比降较小,最大水面比降为-1.9‰。  相似文献   

6.
彭伟  詹锐彪  王斐 《水运工程》2017,(12):169-173
针对沙溪口水电站坝下河段存在的枯水期船闸门槛水深及航道水深不足、流速大流态紊乱的碍航问题,采取筑坝、新建明渠及炸礁相结合的整治思路,调节左右汊分流比,抬高枯水期船闸出口水位,增加航道水深,调整流态,改善船舶航行条件。采用1∶50正态物理模型对航道整治方案进行试验研究,并根据设计方案存在的问题进行多方案研究分析,优化后方案船闸门槛水深、航道水深、流速及流态满足设计要求。  相似文献   

7.
针对龙溪口航电枢纽工程施工明渠临时通航问题,基于数学模型及实船试验,研究施工明渠局部疏浚淤积后船舶临时通航的水流条件及船舶试航情况。数学模型模拟了施工明渠局部清淤形成的临时航道的水深及流速,均满足船舶安全航行要求。不同吨级船舶装载及空载条件下,试验的实船可安全上下行通过龙溪口施工明渠临时航道,为枢纽建设过程临时航道通航范围及尺度的确定提供依据。  相似文献   

8.
针对鄱阳湖水利枢纽通航水流条件是否满足通航安全要求展开研究,建立鄱阳湖入江水道星子—湖山段物理模型,对鄱阳湖水利枢纽一期围堰阶段现状航道、二期围堰及运营期设计航道各典型工况下的通航水流条件进行试验研究。首先通过物理模型试验验证航道内是否产生不良流态;其次针对航道内出现的不良流态提出相应优化措施并进行方案比选;最后对优化后航道内通航水流条件进行试验验证以确保船舶安全通航。模型试验主要结论:二期围堰及运营期设计航道在大流量工况下存在上游口门区横向流速超标及下游锚地段生成大尺度回流等问题。通过实施调整上游隔流堤形式,航道右侧浅滩开挖,下游锚地段下移等措施后,设计航道各工况下水流条件均满足通航安全要求。  相似文献   

9.
窄深急弯河道下游河道主流偏向凹岸下游一侧,下游已建枢纽在同侧布置引航道则存在上引航道占据河道过流面积较大、流速指标超标严重等问题。采用整体定床物理模型及船模试验,研究窄深河道急弯下游枢纽二线船闸上游引航道的布置及其通航水流条件。结果表明,受窄深河道枢纽上游急弯和长引航道分隔墙占据深泓的影响,设计方案中的船闸上引航道口门区通航水流条件较差,不能满足船舶安全航行要求。优化方案在原方案基础上设置堤头下挑单潜坝,优化右岸河段开挖范围及形式,改变隔流墙长度以及隔流墙透空等措施,较好地改善了口门区通航水流条件并兼顾枢纽的行洪和发电,实现船舶安全通航和枢纽正常运行。  相似文献   

10.
采用正态物理模型对依兰航电枢纽下坝线施工一期春汛围堰、主围堰及施工二期通航水流条件进行试验研究。经过多方案比较,提出了经济合理的施工期通航工程措施。结果表明:施工一期春汛围堰、主围堰均壅高了上游水位,同时改变了水流流速分布。施工二期船闸及整治工程建成后,船闸试通航期上下游引航道口门区及连接段通航水流条件基本满足要求,洪水期仅下游连接段纵向水流流速偏大。  相似文献   

11.
Errata     
正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.  相似文献   

12.
13.
正St.John's,Newfoundland,Canada,May 31-June 5,2015 OMAE2015 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to: meet and present advances in technology and its scientific support;  相似文献   

14.
联合作战计划和执行系统   总被引:2,自引:1,他引:1  
全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划:时间不限的精密预案计划生成作战计划、方案计划或职能计划;时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础,加速应付危机的能力。  相似文献   

15.
In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama?
The answer is China South Port Group (Hong Kong, Shenzhen and Guangzhou).  相似文献   

16.
Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form.  相似文献   

17.
桥梁防撞设施物理模型试验   总被引:1,自引:0,他引:1  
物理模型试验是预报防撞设施所受撞击力及优化设计方案的主要方法之一。结合杭州湾大桥柔性防撞设施及东海大桥独立式防撞体设计方案,阐述了船—防撞体撞击试验的基本原理、方法、试验方案及相关试验结果。提出了柔性防撞系统的优化方案。试验结果表明,该方案经济有效,可供预报类似桥梁防撞设施撞击力时参考。  相似文献   

18.
詹明  郑厅厅 《港工技术》2010,47(4):17-19,23
印尼某电厂项目码头水工建筑物包括码头、防波堤和护岸等主要组成部分。在该项目水工建筑物的设计过程中,综合考虑当地的自然条件、施工能力和材料来源等因素,不断优化结构选型和结构断面。根据不同使用要求,护岸分别采用直立式和斜坡式2种结构型式,推荐的设计方案节省投资、施工方便,可供同类工程设计参考。  相似文献   

19.
Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.  相似文献   

20.
开放式数据挖掘系统模型   总被引:2,自引:0,他引:2  
目前国内已经出现了少量的数据挖掘相关产品。国内数据挖掘软件无论从数量还是质量上比较,都与国外软件存在着较大的差距。随着数据仓库技术的普及,数据挖掘应用的需求越来越强烈,如何缩短这种差距,研发数据挖掘软件产品成为国内业界的一个重要问题。通过引用目前国际通用数据挖掘标准技术来构建开放式的数据挖掘系统模型,该系统模型从可扩展性、可重用性、易用性等方面得到了加强。  相似文献   

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