水利水电工程毕业设计英文翻译混凝土重力坝.docx
- 文档编号:1358740
- 上传时间:2022-10-21
- 格式:DOCX
- 页数:6
- 大小:20.96KB
水利水电工程毕业设计英文翻译混凝土重力坝.docx
《水利水电工程毕业设计英文翻译混凝土重力坝.docx》由会员分享,可在线阅读,更多相关《水利水电工程毕业设计英文翻译混凝土重力坝.docx(6页珍藏版)》请在冰豆网上搜索。
水利水电工程毕业设计英文翻译混凝土重力坝
ConcreteGravityDam
Thetypeofdamselectedforasitedependsprincipallyontopographic,geologic,hydrologic,andclimaticconditions.Wheremorethanonetypecanbebuilt,alternativeeconomicestimatesarepreparedandselectionisbasedoneconomicaconsiderations.Safetyandperformanceareprimaryrequirements,butconstructiontimeandmaterialsoftenaffecteconomiccomparisons.
DamClassification
Damsareclassifiedaccordingtoconstructionmaterialssuchasconcreteorearth.Concretedamsarefurtherclassifiedasgravity,arch,buttress,oracombinationofthese.Earthfilldamsaregravitydamsbuiltofeitherearthorrockmaterials,withparticularprovisionsforspillwaysandseepagecontrol.
Aconcretegravitydamdependsonitsownweightforstructuralstability.Thedammaybestraightorslightlycurved,withthewaterloadtransmittedthroughthedamtothefoundationmaterial.Ordinarily,gravitydamshaveabasewidthof0.7to0.9theheightofthedam.Solidrockprovidesthebestfoundationcondition.However,manysmallconcretedamsarebuiltonpreviousorsoftfoundationsandperformsatisfactorily.Aconcretegravitydamiswellsuitedforusewithanoverflowspillwaycrest.Becauseofthisadvantage,itisoftencombinedwithanearthfilldaminwidefloodplainsites.
ArchdamsarewellsuitedtonarrowV-orU-shapedcanyons.Canyonwallsmustbeofrocksuitableforcarryingthetransmittedwaterloadtothesidesofthecanyonbyarchaction.Archsectionscarrythegreatestpartoftheload;verticalelementscarrysufficientloadthroughcantileveractiontoproducecantileverdeflectionsequaltoarchdeflections.Ordinarily,thecrestlength-to-heightratioshouldbelessthan5,althoughgreaterratioshavebeenused.Generally,thebasewidthofmodernarchdamsis0.1to0.3theheightoftheimpoundedwater.Aspillwaymaybedesignedintothecrestofanarchdam.
Multiplearchessimilarlytransmitloadstotheabutmentorendsofthearch.Thistypeofdamissuitedtowidervalleys.Themainthrustandradialshearsaretransmittedtomassivebuttressesandthenintothefoundationmaterial.
Buttressdamsincludeflat-slab,multiple-arch,roundhead-buttress,andmultiple-dometypes.Thebuttressdamadaptstoallsitelocations.Downstreamfaceslabsandapronsareusedforoverflowspillwayssimilartogravitydamspillways.Inclinedslidinggatesorlight-weightlow-headgatescontroltheflow.
Thewaterloadsaretransmittedtothefoundationbytwosystemsofload-carryingmembers.Theflatslabs,arches,ordomessupportthedirectwaterload.Thefaceslabsaresupportedbyverticalbuttresses.Inmostflat-slabbuttressdams,steelreinforcementisusedtocarrythetensionforcesdevelopedinthefaceslabsandbuttresssupports.Massive-headbuttresseseliminatemosttensionforcesandsteelisnotnecessary.
Combiantiondesignsmayutilizeoneormoreofthepreviouslymentionedtypesofdams.Forexample,studiesmayindicatethatanearthfilldamwithacenterconcretegravityoverflowspillwaysectionisthemosteconomialinawide,flatvalley.Otherdesignconditionsmaydictateamultiple-archandbuttressdamsectionorabuttressandgravitydamcombination.
SiteExploration
Thedamlocationisdeterminedbytheproject’sfunctions.Theexactsitewithinthegenerallocationmustbedeterminedbycarefulprojectconsiderationandsystematicstudies.
Inpreliminarystudies,twoprimaryfactorsmustbedetermined-thetopographyatthesiteandcharacteristicsofthefoundationmaterials.Thefirstchoiceofthetypeofdamisbasedprimarilyonthesetwofactors.However,thefinalchoicewillusuallybecontrolledbyconstructioncostifothersitefactorsarealsoconsidered.
Asiteexplorationrequiresthepreparationofanaccuratetopographicmapforeachpossiblesiteinthegenerallocation.Thescaleofthemapsshouldbelargeenoughforlayout.Explorationprimarilydeterminestheconditionsthatmakesitesusableorunusable.
Fromthesiteexplorations,tentativesketchescanbemadeofthedamlocationandprojectfeaturessuchaspowerplants.Physicalfeaturesatthesitemustbeascertainedinordertomakeasketchofthedamanddeterminethepositionofmaterialsandworkplantduringconstruction.Otherfactorsthatmayaffectdamselectionareroadways,fishways,locks,andlogpassages.
Topography
Topographyoftendeterminesthetypeofdam.Forexample,anarrowV-shapedchannelmaydictateanarchdam.Thetopographyindicatessurfacecharacteristicsofthevalleyandtherelationofthecontourstothevariousrequirementsofthestructure.Soundnessoftherocksurfacemustbeincludedinthetopographicstudy.
Inalocationstudy,oneshouldselectthebestpositionforthedam.Anaccuratesketchofthedamandhowitfitsintothetopographicfeaturesofthevalleyareofte
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 水利水电工程 毕业设计 英文翻译 混凝土 重力坝