简介：存在抵抗公式为石子床溪流生产大量磨擦因素估计。这份报纸的目的是以Darcy-Weisbach磨擦因素f开发一个可靠抵抗公式。出版数据被屏蔽并且过去常建立公式。存在公式认为f仅仅是相对粗糙D84/R的功能，在R是水力的半径，D84是指的粒子尺寸的地方等于或超过84%床沉积的中间的直径。在这份报纸，f除了相对粗糙被看作弗鲁德数字的功能。为D84/R的f>1为D84/R比那显示一个不同趋势<1也许由于为D84/R的对数的速度分布的无效假设>1。为D84/R的一个f公式<1被建立了。

简介：Depositionofcoarsesedimentattheentranceofareservoirisformanyreasonsanundesiredsideeffect.Besideslossofstoragevolumewhichconcernsalsofinesedimentcarriedinsuspension,thecoarsermaterialtransportedasbedload-particularlythegravelfraction-istocauseadditionaleffectsupstreamaswellasdownstreamofthereservoir.Upstreamthedepositionsattheentranceofthereservoirmayresultinabackupeffectatfloodeventswithincreasingriskofinundations,anddownstreamofthereservoirthedeficiencyofcoarsematerialinevitablyresultsindegradationoftheriverbed.Intheframeofarealhydropowerplant(BadTOlzinSouthernBavaria)thepossibilityofsluicingcoarsematerialthroughthereservoirtowardsdownstreamhasbeenstudiedandfinallyrealized.Thesluicingprocesshasbeencoupledwithwaterleveldrawdownatfloodeventsofappropriatecharacteristics.Thesluicingactionwascontrolledbymonitoringandevaluatingenvironmentallysignificantparameters(sedimentconcentration,etc.).Theresultswerepromisingandvaluablehintsforfurtheractionsofthiskindcouldbeextracted.

简介：ResearchwascarriedoutattheUniversityofKarlsruheinthelast10yearstomodifyexistingformulasandimproveourknowledgeonthedeterminationofthestabilityofstreambedsconsistingofgravelsandstones.StreamsinthemiddlemountainregionwithtypicalslopesofI=0.05%to0.8%aswellasthosewithdistinctstep-poolstructuresandslopesofI＞4%andI≤10%wereinvestigated.MostoftheexperimentswereconductedintheTheodor-RehbockLaboratory.However,someoftheresultsthathadbeenobtainedunderlaboratoryconditionscouldbeverrifiedwithexistingfielddata.Inthefollowing,theresultsandformulasofpracticalimportancewillbeintroducedanddiscussed.

简介：这篇论文论述实验室斜槽的结果流动速度上的银行植被和石子床的相互作用上的试验性的学习(首先在最大的速度的地点上，Umax)并且雷纳兹压力分布。结果表明在水表面下面的最大的速度的剧降直到在Umax之间的35%流动深度和差别，在水表面的速度面对墙上的植被是可观的。木头法律的地区从墙从多达15%流动深度和它不取决于的y/h=2改变距离。没有植被盖子，在在有墙上的植被盖子的一张石子床上的外部层的速度侧面的偏差比在一张石子床上的流动的盒子大得多。墙上的植被的存在把一致流动改变到不一致的流动。这个事实能被越过斜槽在不同距离在每侧面认为非线性的雷纳兹是压力分发和最大的速度的地点解释。在距离的雷纳兹压力分布从墙的0.02m有否定价值并且离开墙，他们改变在更高的地点与顶与特定的凸的形式拿积极价值的符号。为这研究的vonKarman经常的κ的一般水准等于0.16。基于κ=0.16，Clauser的方法和雷纳兹压力为决心是兼容的砍速度。

简介：Researchsamplesweretakenfromanancientgravelstratumwhichisnotonlyarepresentativesoillayeralongthemiddle-lowerreachesoftheYangtzeRiverinEastChina,butalsooneoftheprimaryNeozoicstratainNanjingdistrict.Locatedmostlyonthesecondandthirdterraces,theancientgravelstrataformedthegeomorphiclandscapesofterraceandstep.Theywerecomplexinconstitution,variedwidelyinstability,ofmultiplesources,locallyderived,andassociatedwithbraidedstreamsinthedepositionenvironment.ACIPW(Cross,Iddings,PirssonandWashington)methodmodifiedbytheauthorwasusedtoanalyzethesoi-rock-formingmaterialsoffinergrains(lessthan2mminsize)oftheancientgravelstratum.Resultsoftheanalysisshowedthatthesandygrainswerecomposedofapatite,ilmenite,potassiumfeldspar,plagioclase,enstatiteandfreequartz,theclaymainlyofkaolinite,andthecementofacombinationofsilicon,aluminumandironataratioof46:44:10.Inthesoil-rock-formingprocesses,includingcompactionalsolidification,water-stableilluviation-cementation,homogeneousovergrowthandsoon,theloosesoil-rock-formingcomponentsgraduallychangedintoconsolidatedsoilandfurthertotheearlystageoflithification.Meanwhile,fromtheanalysis,wefoundthattheancientgravelstratumhadbeenprotectedbytheoverlyingXiashuloessorbasaltandtheoverloadingresultedinoverconsolidatedstrata.ThemodifiedCIPWmethodwasapplicableandeffectiveforsemi-quantitativeanalysis.

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简介：Thedynamicshearmodulusratioanddampingratioofsandygravelareimportantparametersfortheseismicresponseanalysisofvalleygeomorphicsites,whichhaveanimportantimpactonthedeterminationofdesigngroundmotionparameters.Inthispaper,thedynamictriaxialtestofsandygravelshasbeenperformedbasedontheprojectoftheShangluoSeismicMicrozonation.Combinedwiththeotherresultsofsandygravel,therecommendedresultsofslightlydense,mediumdenseanddensesandygravelwereobtained.Bybuildingthetypicalsitemodel,theinfluenceofthedynamicshearmodulusratioandthedampingratiouncertaintyontheseismicresponseofthesiteisstudied.Theresultsshowthattheuncertaintyoftheaverageofthedynamicshearmodulusratioandthedampingratio±1timesthestandarddeviationhaslittleeffectonthepeakaccelerationofthesandygravelsite,andtherationalityofthegroupingandstatisticalresultsisexplained.Underdifferentprobabilitylevels,thechangeintheshearmodulusratioanddampingratioleadstoasignificantdifferenceinthehighfrequencyresponsespectrum.Theresponsespectrumof0.04-0.1srangesfromabout20%,butithaslittleeffectonthelongperiodspectrumofmorethan1.0s.Thestudyofdynamicshearmodulusratioanddampingratioofsandygravelhastheabilitytoimprovethereliabilityofthedesigninggroundmotionparameters.

简介：深度有限的实验室实验在一张石子床上的开隧道的流动在学习被进行。有相同单个元素尺寸和不同长度(3.81m和7.5m)的二个石子补丁被测试。有亲戚的深度有限制服流动政体浸没Sr(=D/k从2.68～5.94的s)被调整尾板堰生产。速度侧面被使用一个超声速度剖析程序(UVP)和声学的Doppler速度计(副词)测量。过去常决定零飞机的排水量并且估计床的常规方法砍速度然后被考察并且比较。测量双averaged(DA)速度侧面被发现与一个非通用的Karman常数与木头法律和缺点法律适合很好。将近经常的价值遗体并且在为长补丁(LP)的从0.2～0.3的范围，盒子和价值为短补丁(SP)从0.3～0.5在一个更宽的范围以内被散布盒子。当在木头法律的Br值为LP诉讼仍然保持对8.5不变、相等时，Br值被发现随无尺寸的粗糙高度k为SP诉讼的s+。streamwise骚乱紧张分布被发现在补丁长度上独立并且在中间的区域和墙区域与可得到的试验性的数据同意很好。曼宁抵抗系数和DarcyWeisbach磨擦因素被分析。为在小亲戚下面的对数的流动抵抗法律的试穿的到0.22的价值减少浸没。在对数的法律的集成常数Ar的价值在在3.25和6.25之间的正常范围以内掉落。

简介：Synchronouschipsealisanadvancedroadconstructingtechnology,andthegravelcoveragerateisanimportantindicatoroftheconstructionquality.Inthispaper,anovelapproachforgravelcoverageratemeasurementisproposedbasedondeeplearning.Convolutionalneuralnetwork(CNN)isusedtosegmenttheimageofgroundcoveredwithgravels,andthegravelcoveragerateiscomputedbythepercentageofgravelpixelsinthesegmentedimage.Thegravelcoverageratedatasetformodeltrainingandtestingisbuilt.Theperformanceoffullyconvolutionalneuralnetwork(FCN)andU-Netmodelinthedatasetistested.AbettermodelnamedGravelNetisconstructedbasedonU-Net.Thescaledexponentiallinearunit(SELU)isemployedintheGravelNettoreplacethepopularcombinationofrectifiedlinearunit(ReLU)andbatchnormalization(BN).Dataaugmentationandalphadropoutareperformedtoreduceoverfitting.Theexperimentalresultsdemonstratetheeffectivenessandaccuracyofourproposedmethod.OurtrainedGravelNetachievesthemeangravelcoveragerateerrorof0.35%ontestdataset.

简介：FieldexperimentswereconductedontotalloadtransportintheChelichayRiverBasin,amountainouscatchment(1,400km~2)locatedinnortheasternofIran,toevaluatetotalloadformulasincludingfourgravelbedriversandasandbedriver(QaresooRiver).GravelbedriversinChelichayRiverBasincanbegroupedintotwotypes;steepsloperiverswithhighshearvalues(ChehelchayRiverandKhormalooRiver)andmildsloperiverswithlowshearvalues(NarmabRiverandSoosaraRiver).Twodepthintegratingsuspendedloadsamplers(DH-48andD-49),andtwobedloadsamplers(Helley-SmithandBLSH)wereusedtomeasuretotalload.Theperformanceistestedof8totalloadtransportformulaeincluding4macroscopicand4microscopicmethods.Asystematicandthoroughanalysisof59setsofdatacollectedfromsandbedriverindicatethatYangandEngelundandHansenreachtothebetterresults,andfromfourgravelbedriversconfirmedthatthemethodsofKarimandKennedyandEngelundandHansenyieldsthebestresultsforsteepsloperivers,andthemethodsofEinsteinandBijkerarerankedhighestingradualsloperivers.

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