振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2014年
1期
45-50
,共6页
悬挂式人行桥%基频%车桥耦合振动%行人舒适性
懸掛式人行橋%基頻%車橋耦閤振動%行人舒適性
현괘식인행교%기빈%차교우합진동%행인서괄성
suspended pedestrian bridge%fundamental frequency%vehicle-bridge coupling vibration%pedestrian comfort
将人行桥作为车行主桥的悬挂结构,形成一个组合式桥梁,共同解决人车通行问题,然而这种结构形式在主桥车辆荷载激励下人行桥的振动舒适性还有待研究。首先推导了悬挂式人行桥的基频估算公式并通过有限元计算进行了验证,研究表明悬挂式人行桥的基频很大程度上取决于车行主桥的自振特性。采用分离迭代法对某悬挂式人行桥的车致振动响应进行了分析,结果表明车行桥路面粗糙度、车速、车流密度等都会显著影响车辆通过时桥梁的振动响应,车致振动引起的人行桥跨中竖向峰值加速度可达到仅人行激励引起的相应值的一半以上,悬挂式人行桥行人舒适性评价中应考虑会降低其舒适度的车致振动效应的影响。
將人行橋作為車行主橋的懸掛結構,形成一箇組閤式橋樑,共同解決人車通行問題,然而這種結構形式在主橋車輛荷載激勵下人行橋的振動舒適性還有待研究。首先推導瞭懸掛式人行橋的基頻估算公式併通過有限元計算進行瞭驗證,研究錶明懸掛式人行橋的基頻很大程度上取決于車行主橋的自振特性。採用分離迭代法對某懸掛式人行橋的車緻振動響應進行瞭分析,結果錶明車行橋路麵粗糙度、車速、車流密度等都會顯著影響車輛通過時橋樑的振動響應,車緻振動引起的人行橋跨中豎嚮峰值加速度可達到僅人行激勵引起的相應值的一半以上,懸掛式人行橋行人舒適性評價中應攷慮會降低其舒適度的車緻振動效應的影響。
장인행교작위차행주교적현괘결구,형성일개조합식교량,공동해결인차통행문제,연이저충결구형식재주교차량하재격려하인행교적진동서괄성환유대연구。수선추도료현괘식인행교적기빈고산공식병통과유한원계산진행료험증,연구표명현괘식인행교적기빈흔대정도상취결우차행주교적자진특성。채용분리질대법대모현괘식인행교적차치진동향응진행료분석,결과표명차행교로면조조도、차속、차류밀도등도회현저영향차량통과시교량적진동향응,차치진동인기적인행교과중수향봉치가속도가체도부인행격려인기적상응치적일반이상,현괘식인행교행인서괄성평개중응고필회강저기서괄도적차치진동효응적영향。
A pedestrian bridge suspended to a vehicular bridge to form a combined bridge,can provide passages not only for vehicles but pedestrians.However,the vibration comfort of the suspended pedestrian bridge under vehicle excitation from the vehicular bridge still needs to be discovered.Fundamental frequency estimation formulas for the suspended pedestrian bridge were proposed and verified through finite element method.The results show that fundamental frequencies of the suspended pedestrian bridge depend largely on dynamic characteristics of the vehicular bridge.The vehicle induced vibration of a long-span suspended pedestrian bridge was analyzed by using separated iteration methods. The results show that the vibration responses become larger with worse road condition or higher density traffic flow.The vibration responses have no evident relationship with vehicle speed.The vertical acceleration peak of the pedestrian bridge in mid-span under vehicle excitation exceeds half of that excited by pedestrians.Therefore,the vehicle induced vibration effect should be considered in the comfort evaluation of pedestrian bridges suspended to vehicular bridges.