Page 45 - 2023年第54卷第8期
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Studyonpredictingthecompacteddensityofrockfillmaterialsbased
onthegranularpackingalgorithm
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SHENChaomin ,DENGGang,LIUSihong,YANJun,MAOHangyu,WANGLiujiang 1
(1.CollegeofWaterConservancyandHydropowerEngineering,HohaiUniversity,Nanjing 210098,China;
2.KeyLaboratoryofConstructionandSafetyofWaterEngineeringofMinistryofWaterResources,
ChinaInstituteofWaterResourcesandHydropowerResearch,Beijing 100048,China)
Abstract:Thecompacteddensityofrockfillmaterialsisanimportantindextoreflecttheirengineeringandme
chanicalproperties.Anumericalgranularpackingalgorithm ,whichisbasedonthedimension - reductionmapping
andcontainsonlyoneparameter ,isproposedtodeterminethemaximum densityofrockfillmaterialsinrealtime
whentheparticlesizedistributionsisgiven.Comparedwiththeexperimentalresultsintheliterature ,theproposed
algorithmcanpredictthemaximumdensityofbothwell - gradedandgap - gradedrockfillmaterials,whichprovides
anewideafortheeffectiveoptimizationofthegradingcurveofrockfillmaterials.Theeffectsoffinestruncationand
downscalingonthecompacteddensityareanalyzedusingtheproposedalgorithmanditisfoundthat :theproposed
methodcanwellpredictthecompacteddensityoftheprototyperockfillmaterialsbasedontheresultofthedown
scaledsample.Theperformanceofthepredictionofthescaleeffectisinfluencebythefinestruncation,andtheer
rorofthepredictedcompacteddensifyisproportionaltothefinescontent ;Fromthepointofviewofgranularpack
ing ,theskeletonvoidsofcoarsecontentdecreasesforthedownscaledspecimens,disfavoringthefillingoffines,
whiletheincreasingfinescontentwiththedownscalingprocedurehasnoconsistenteffectonthecompacteddensity
ofrockfillmaterials,anddependsonboththeparticlesizedistributionsofboththecoarseandfineparticles.
Keywords:rockfillmaterials;granularpacking;maximumdensity;scaleeffect;particlesizedistribution
(责任编辑:李 娜)
(上接第 919页)
Studyonwave - dampingcharacteristicsofrigidplantsintidalflats
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ZHANGZhilin 1,2,3 ,HUANGBensheng 1,2,3 ,LIUDa ,QIUJing
(1.GuangdongResearchInstituteofWaterResourcesandHydropower,Guangzhou 510635,China;
2.StateandLocalJointEngineeringLaboratoryofEstuarineHydraulicTechnology,Guangzhou 510635,China;
3.SouthernMarineScienceandEngineeringGuangdongLaboratory(Zhuhai),Zhuhai 519082,China)
Abstract:Theplantsintidalflatsarebeneficialtowatersecurityincoastalareas,andquantifyingthewaveat
tenuationeffectofmatureplantsisthebasisforimprovingtheresilienceofthecoasts.Basedongeneralrulesand
twowaveattenuationmodels ,thispaperhasputforwardanewmethodforcalculatingthewaveattenuationcoeffi
cientofplantsintidalflats,whichcanbeusedtocalculatethewaveheightbehindplants.Then,theseexpres
sionshavebeenvalidatedbyalargeamountofexperimentaldata.Finally ,theresultsofwaveheightbehind
plantscalculatedbythismethodhavebeencomparedtothestandardmethod.Theresultsshowthatthedamping
factorandwaveattenuationcoefficientcandirectlyreflectthewaveattenuationcharacteristicsandtheproportionof
plantareatocross - sectionalareainthedirectionofwavepropagationisthekeydimensionlessparameterthataf
fectsthemechanismofwaveattenuationbyrigidplants.Whenplantsemerge ,thecalculatedvalueofthewave
heightbehindplantsbythismethodisclosetothestandardmethod;whilewhenplantsaresubmerged,this
methodcandescribethewaveattenuationmoreaccurately.Comparedtothestandardmethod,thismethodcon
siderstheinfluenceofplantsubmergence ,andintuitivelyrevealstheinfluenceofthedensity,width,heightof
thecanopy ,averagediameterofplants,waterdepth,andotherparameters,makingitsuitableformorecondi
tions.Amodelbasedonthismethodcanbeusedtoestimatetheimpactofrelevantparametersonthewaveattenu
ationbyplants ,whichcanprovideasignificantbasisfortheplanninganddesignofrigidplantsintidalflatsand
relatedmathematicalmodelresearch.
Keywords:waveattenuationbyplant;waveattenuationmodels;waveattenuationcoefficient;dragcoefficient;
physicalmodeltests
(责任编辑:李福田)
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