橋梁斷面三自由度顫振導(dǎo)數(shù)識(shí)別.pdf

1、同濟(jì)大學(xué)碩士學(xué)位論文橋梁斷面三自由度顫振導(dǎo)數(shù)識(shí)別姓名：何憲飛申請學(xué)位級別：碩士專業(yè)：橋梁與隧道工程指導(dǎo)教師：陳艾榮項(xiàng)海帆2001.3.1AbstractIdenti6catioⅡof18FlutterDerivativesofBridgeDecksABSTRACTTheaerodynamicselfexcitedforcescanbedescribedin18flutterderivativesHowever，outoftheentir

2、ecomplementof18flutterderivatives，only68derivativeshavebeenexperimentallydeterminedinmostwindtunneltestingsWiththecurrenttrendofincreasingspansofbridges，thelateralderivativesofbridgedecksplaymoreandmoreimportantrolesinfl

3、utteranalysisoflong—spanbridgesBasedontheexistingidentificationtheoryandexperimentalsystemof2DOFsectionalmodels，generalleastsquaretheoryandexperimentalsystemofbridgedecksectionsforidentifying18flutterderivativesaredevelo

4、pedinthispaperFurthermore，thenoiseinmeasureddataisconsideredintheidentilyingmethod，whichimprovetheaccuracyofidentificationofflutterderivativesAll18flutterderivativesofbridgedecks，suchasaplatesectionastreamlinedboxgirders

5、ectionanda玎一shapesectionareobtainedfromthefreevibrationtimehistoriesofmotionswiththegeneralleast—squaretheoryThederivativesfrom3DOFexperimentarecomparedwiththeresultsfromCFDmethodFurthermore，theestimatedvaluesbasedonthep

6、seudo—steadyformulationareverifiedwiththeexperimentalresultsInordertodisplaytheruleoflateralflutterdeftvatives，theeffectofshapesofsections，andwindincidenceanglesaswellasrailingsonderivativesarediscussedinthesectionalmode

7、lexperimentsAtlast，acomplexmodeiterationmethodologyisdevelopedforcalculatingthecriticalflutterwindspeedofa3DOFsystemandthefluttermechanismfora3DOFsystemiselementarilyexplainedthroughtheflutteranalysisofbridgeswiththreedi