Page 110 - 2023年第54卷第6期
P. 110
2002,24(3):219 - 226.
[24] DINGYJ,LIUSY,LIJ,etal.TheretreatofglaciersinresponsetorecentclimatewarminginwesternChina
[J].QuaternarySciences.2006,1(43):97 - 105.
Researchonheattransfercharacteristicsongroundsurfaceandthermalboundary
settingmethodincentrifugaltestsforcoldregionsengineering
2
1
1
ZHANGChen,CHENHongyong,WANGYi,CAIZhengyin 1
(1.NanjingHydraulicResearchInstitute,Nanjing 210024,China;
2.InstituteofSystemsEngineering,ChineseAcademyofEngineeringPhysics,Mianyang 621000,China)
Abstract:Theaccuratesimulationoftemperaturefieldisthekeytocarryoutgeotechnicalcentrifugaltestsforcold
regionsengineering.Neglectingthesettingofthermalboundaryconditionsinmosttestswhereusingsemiconductor
refrigerationdevices ,whichmakesitdifficulttoensuretheaccuracyofthetest.Inordertoimprovetherationality
andaccuracyoftests ,thefiniteelementCFDmethodwasusedtosimulatetheheattransferprocessintheconfined
spaceunderthesupergravityfield.Bychangingthemainboundaryconditionssuchasmodelscale (acceleration),
outputtemperatureandgapspacing,theheattransfercharacteristicsandtheirspace - timelawsbasedonsemicon
ductorheatexchangerareclarified.Onthisbasis,combinedwiththecharacteristicsoftheequipmentandtruecon
ditions ,thetemperatureboundaryofthemodelisdescribedbytheairfreezingindex,astheoptimalindexfor
matchingprototypetemperatureatgeotechnicalcentrifugaltestsforcoldregionsengineering ,whichspecifyingthe
heatboundaryparametersettings.
Keywords:coldregionsengineering;centrifugaltest;heattransfer;temperatureboundary;freezingindex
(责任编辑:李 娜)
(上接第 716页)
Effectsoffreezing - thawingactiononthemacro - micropropertiesof
bankslopesoilandbankstability
1
1
1
1
YANGZhen,JIHonglan,LIChao,MOUXianyou,LIBashuan 2
(1.CollegeofWaterResourcesandCivilEngineering,InnerMongoliaAgriculturalUniversity,Hohhot 010018,China;
2.HohhotTuoketuoCountyRuralRevitalizationCoordinatedDevelopmentCenter,Hohhot 010200,China)
Abstract:Freeze - thawactionisthemainfactorofbankslopeinstabilitydamageintheseasonalfreezingzone.
TakingthebankslopesoilofShisifenzibendinInnerMongoliaoftheYellowRiverastheresearchobject ,themac
roscopicandmicroscopicpropertiesofthebankslopesoilunderfreeze - thawactionwerestudiedbytriaxialshear
andscanningelectronmicroscopetests ,andthestabilityofthebankslopebeforeandafterfreeze - thawwasana
lyzedbasedonthestrengthreductionmethod.Theresultsshowthatthemodulusofelasticity ,cohesionandshear
strengthofthesoildecreasewiththeincreaseofthenumberoffreeze - thawcycles,amongwhichthesizeofthe
modulusofelasticityisinverselyproportionaltothemoisturecontent,thecohesiondecreasesby43.6%~60.04%
after15freeze - thawcycles ,andtheangleofinternalfrictionhasnoobviouschangepattern.Soilparticleroundness
andporeprobabilityentropydecreasedandthenincreasedwiththeincreaseofthenumberoffreeze - thawing ,while
thechangetrendofparticlefractaldimensionisopposite ,andsoilorientationandporosityshowedanincreasing
trend.Cohesioniscorrelatedwithsoilporosityandparticleroundness ,andespeciallyhighlynegativelycorrelated
withporosity ,andthereisasignificantautocorrelationbetweensoilmicroparameters.Thestabilitysafetyfactorof
thebankslopeafterfreeze - thawdecreasesby41.8%,indicatingthatthefreeze - thawactionwillsignificantly
reducethestabilityofthebankslope,andthebankslopeispronetoinstabilitydamageafterfreeze - thaw.
Keywords:freeze - thawcycles;shearstrengthindex;microstructure;bankstability;InnerMongoliareachof
theYellowRiver
(责任编辑:李福田)
— 7 3 —
8