振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2015年
2期
176-181
,共6页
Π型截面%叠合梁斜拉桥%涡振%气动控制%风洞试验
Π型截麵%疊閤樑斜拉橋%渦振%氣動控製%風洞試驗
Π형절면%첩합량사랍교%와진%기동공제%풍동시험
Π shaped deck%cable-stayed bridge with composite beam%vortex-induced vibration%aerodynamic control%wind tunnel test
为研究Π型开口截面主梁的涡振性能并提出合理性控制措施,以某跨海叠合梁斜拉桥为研究对象,进行一系列节段模型风洞试验。研究表明,Π型开口截面主梁在低风速下易发生涡激共振,且该桥涡振现象在阻尼比<1%以下范围内均存在;桥面防撞栏杆及检修道护栏采用圆截面形式有利于减小涡振振幅;改尖角度风嘴能显著抑制涡激共振,且风嘴角度越小控制效果越好;桥梁断面底部双主肋转角处设置水平隔流板能有效减小甚至消除涡激振动,在一定范围内增加板的悬挑宽度对控制效果有利。
為研究Π型開口截麵主樑的渦振性能併提齣閤理性控製措施,以某跨海疊閤樑斜拉橋為研究對象,進行一繫列節段模型風洞試驗。研究錶明,Π型開口截麵主樑在低風速下易髮生渦激共振,且該橋渦振現象在阻尼比<1%以下範圍內均存在;橋麵防撞欄桿及檢脩道護欄採用圓截麵形式有利于減小渦振振幅;改尖角度風嘴能顯著抑製渦激共振,且風嘴角度越小控製效果越好;橋樑斷麵底部雙主肋轉角處設置水平隔流闆能有效減小甚至消除渦激振動,在一定範圍內增加闆的懸挑寬度對控製效果有利。
위연구Π형개구절면주량적와진성능병제출합이성공제조시,이모과해첩합량사랍교위연구대상,진행일계렬절단모형풍동시험。연구표명,Π형개구절면주량재저풍속하역발생와격공진,차해교와진현상재조니비<1%이하범위내균존재;교면방당란간급검수도호란채용원절면형식유리우감소와진진폭;개첨각도풍취능현저억제와격공진,차풍취각도월소공제효과월호;교량단면저부쌍주륵전각처설치수평격류판능유효감소심지소제와격진동,재일정범위내증가판적현도관도대공제효과유리。
To study the vortex-induced vibration (VIV)and its control measures for the bridge with Π shaped deck,the aerodynamic performance of a cross-sea cable-stayed bridge was investigated through section-model wind tunnel tests.The results show that the Πshaped deck concerned suffers remarkable VIV at low wind velocity,which exists under the structural damping ratio of 1%.Crash barrier and maintenance way railings with cylinder shape are conducive to decrease VIV amplitude,both vertical and torsional.The VIV can be mitigated via sharpening wind fairings and the vibration mitigation effect is more significant with smaller wind fairing angle.The horizontal flow-isolating plate (HFIP), jutting out of the inner edge of the girder bottom plates,can mitigate and even eliminate the VIV effectively.Generally, within certain limits,the wider the HFIP,the better the mitigation effect.