赤石特大桥索塔三分力系数识别与抗风时程分析
|
摘要
介绍风速时程模拟方法,特别针对谐波合成法进行论述。以赤石特大桥为例,采用Fluent软件进行-4°～4°攻角范围内特定截面的三分力系数模拟分析,结果表明,当攻角为1°时,阻力系数最大。根据现场采集的风速样本,针对5号塔进行抗风时程分析,研究结果表明:采用不同的计算标准,动力系数结果并不一致,甚至当以横桥向弯矩为标准,脉动风荷载作用下索塔没有表现出动力放大效应;在桥面脉动风荷载作用、塔顶脉动风荷载作用下,塔顶的最大位移、索塔底部最大应力均在容许范围之内;索塔横桥向刚度远大于顺桥向,抗风分析应以顺桥向为主;采用不同的标准计算动力系数结果不同,进行拟静力分析时建议采用动力系数的最大值。
Wind speed time history simulation methods has been discussed first in this paper, especially for the harmonic synthesis method introduced in detail. Second, taking Chishi super large bridge for example, choosing a particular section, three-component coefficient simulate analysis between -4° and 4° has been carried out with the Fluent software, the results show that when the Angle of attack is 1°, drag coefficient reached maximum; Finally, according to measured wind speed samples, time history curves of wind speed for bridge deck and top of tower have been obtained, and time history analysis of wind-resistant for No.5 tower has been carried out. The results show that dynamic coefficients are different with different calculation standard, and even take bending moment cross the bridge for the standard, pulsating wind load does not show a dynamic amplification effect; Under pulsating wind loads at bridge deck or top of the tower, the maximum displacement at the top of the tower and maximum stress at the bottom of the tower are within the allowable range; The stiffness of lateral direction is far greater than that of longitudinal direction, therefore wind-resistant should be give priority to that of longitudinal direction. Dynamic coefficient result is obtained by different standards, maximum power coefficient is recommended for pseudo-static analysis.
Wind speed time history simulation methods has been discussed first in this paper, especially for the harmonic synthesis method introduced in detail. Second, taking Chishi super large bridge for example, choosing a particular section, three-component coefficient simulate analysis between -4° and 4° has been carried out with the Fluent software, the results show that when the Angle of attack is 1°, drag coefficient reached maximum; Finally, according to measured wind speed samples, time history curves of wind speed for bridge deck and top of tower have been obtained, and time history analysis of wind-resistant for No.5 tower has been carried out. The results show that dynamic coefficients are different with different calculation standard, and even take bending moment cross the bridge for the standard, pulsating wind load does not show a dynamic amplification effect; Under pulsating wind loads at bridge deck or top of the tower, the maximum displacement at the top of the tower and maximum stress at the bottom of the tower are within the allowable range; The stiffness of lateral direction is far greater than that of longitudinal direction, therefore wind-resistant should be give priority to that of longitudinal direction. Dynamic coefficient result is obtained by different standards, maximum power coefficient is recommended for pseudo-static analysis.
引文
[1]WANG Aiqin,LI Longan.Evaluation method of wind-resistance capability of large-span bridge on highway[J].Journal of Chang’an University(Natural Science Edition),2006,5(5):59-60.
[2]罗俊杰,韩大建.谐波合成法模拟随机风场的优化算法[J].华南理工大学学报,2007,4(7):14-18.LUO Junjie,HAN Dajian.Optimized algorithm of wave superposition method to simulate stochastic wind field[J].Journal of South China University of Technology(Natural Science Edition),2007,4(7):14-18.
[3]周仁忠,程多云,刘丹.大跨钢桁拱桥悬臂施工法抗倾覆压重控制技术[J].中外公路,2016,36(6):133-137.ZHOU Renzhong,CHENG Duoyun,LIU Dan.Resistance to capsizing control technology of loading for long-span steel truss arch bridge with cantilever construction method[J].Journal of China&Foreign Highway,2016,36(6):133-137.
[4]JTG/T D60-01-2004,公路桥梁抗风设计规范[S].JTG/T D60-01-2004,Wind-resistant design specification for highway bridges[S].
[5]丁泉顺,朱乐东.基于气弹模型试验的高耸结构随机风振等效静力风荷载[J].振动与冲击,2012,31(24):18-22.DING Quanshun,ZHU Ledong.Equivalent static wind loads for stochastic vibration of a towering structure based on its aeroelastic-model wind tunnel test[J].Journal of Vibration and Shock,2012,31(24):18-22.
[6]姚陈果,张薷方.架空输电塔-线体系导线风振对脱冰的影响[J].高电压技术,2014,40(2):37-41.YAO Chenguo,ZHANG Rufang.Influence of wind vibration of overhead transmission tower-line system on ice shedding[J].High Voltage Engineering,2014,40(2):37-41.
[7]王浩,李爱群,杨玉冬,等.中央扣对大跨悬索桥动力特性的影响[J].中国公路学报,2006,6(6):50-52.WANG Hao,LI Aiqun,YANG Yudong,et al.Influence of central buckle on dynamic behavior of long-span suspension bridge[J].China Journal of Highway and Transport,2006,6(6):50-52.
[8]周秀芳,曹树谦.用Normal Form直接法研究壁板的热颤振与控制[J].振动与中击,2012,5(11):54-56.ZHAO Xiufang,CAO Shuqian.Thermal flutter and control of a panel using Normal Form direct method[J].Journal of Vibration and Shock,2012,5(11):54-56.
[9]许福友,陈艾荣,张建仁.缆索承重桥梁的颤振可靠性[J].中国公路学报,2006,4(5):60-61.XU Fuyou,CHEN Airong,ZHANG Jianren.Flutter reliability of cable supported bridge[J].China Journal of Highway and Transport,2006,4(5):60-61.
[10]顾明,黄鹏.群体高层建筑风荷载干扰的研究现状及展望[J].同济大学学报(自然科学版),2003,3(7):762-766.GU Ming,HUANG Peng.Research history and state-of-art of interference effects of wind loads of a cluster of tall buildings[J].Journal of Tongji University(Natural Science),2003,3(7):762-766.
[11]Rowan A I,Stoyan S,XIE J M.Tacoma narrows 50 years later-wind engineering investigations for parallel bridges[J].Bridge Structures:Assessment Design and Construction,2015,2(1):3-17.
[12]BAI Hua,LI Defeng.A study on improving measures for wind-resistance stability of pedestrian suspension bridge[J].Highway,2012,1(12):22-25.
[13]Rowan A I,Stoyan S,XIE J M.Tacoma narrows 50 years later-wind engineering investigations for parallel bridges[J].Bridge Structures:Assessment Design and Construction,2014,3(1):3-17.
[14]Michael C H H,Larsen A.Aerodynamic investigations for the deck of stonecutters bridge emphasizing Reynolds number effects[M].Busan Korea:Elsevier Plublication,2012:649-656.
[15]刘小兵,刘志文,陈政清.双幅桥面桥梁主梁断面的气动选型[J].振动与冲击,2009,28(8):34-37.LIU Xiaobing,LIU Zhiwen,CHEN Zhengqing.Aerodynamic optimization of twin deck bridge girder’s cross section[J].Journal of Vibration and Shock,2009,28(8):34-37.
[2]罗俊杰,韩大建.谐波合成法模拟随机风场的优化算法[J].华南理工大学学报,2007,4(7):14-18.LUO Junjie,HAN Dajian.Optimized algorithm of wave superposition method to simulate stochastic wind field[J].Journal of South China University of Technology(Natural Science Edition),2007,4(7):14-18.
[3]周仁忠,程多云,刘丹.大跨钢桁拱桥悬臂施工法抗倾覆压重控制技术[J].中外公路,2016,36(6):133-137.ZHOU Renzhong,CHENG Duoyun,LIU Dan.Resistance to capsizing control technology of loading for long-span steel truss arch bridge with cantilever construction method[J].Journal of China&Foreign Highway,2016,36(6):133-137.
[4]JTG/T D60-01-2004,公路桥梁抗风设计规范[S].JTG/T D60-01-2004,Wind-resistant design specification for highway bridges[S].
[5]丁泉顺,朱乐东.基于气弹模型试验的高耸结构随机风振等效静力风荷载[J].振动与冲击,2012,31(24):18-22.DING Quanshun,ZHU Ledong.Equivalent static wind loads for stochastic vibration of a towering structure based on its aeroelastic-model wind tunnel test[J].Journal of Vibration and Shock,2012,31(24):18-22.
[6]姚陈果,张薷方.架空输电塔-线体系导线风振对脱冰的影响[J].高电压技术,2014,40(2):37-41.YAO Chenguo,ZHANG Rufang.Influence of wind vibration of overhead transmission tower-line system on ice shedding[J].High Voltage Engineering,2014,40(2):37-41.
[7]王浩,李爱群,杨玉冬,等.中央扣对大跨悬索桥动力特性的影响[J].中国公路学报,2006,6(6):50-52.WANG Hao,LI Aiqun,YANG Yudong,et al.Influence of central buckle on dynamic behavior of long-span suspension bridge[J].China Journal of Highway and Transport,2006,6(6):50-52.
[8]周秀芳,曹树谦.用Normal Form直接法研究壁板的热颤振与控制[J].振动与中击,2012,5(11):54-56.ZHAO Xiufang,CAO Shuqian.Thermal flutter and control of a panel using Normal Form direct method[J].Journal of Vibration and Shock,2012,5(11):54-56.
[9]许福友,陈艾荣,张建仁.缆索承重桥梁的颤振可靠性[J].中国公路学报,2006,4(5):60-61.XU Fuyou,CHEN Airong,ZHANG Jianren.Flutter reliability of cable supported bridge[J].China Journal of Highway and Transport,2006,4(5):60-61.
[10]顾明,黄鹏.群体高层建筑风荷载干扰的研究现状及展望[J].同济大学学报(自然科学版),2003,3(7):762-766.GU Ming,HUANG Peng.Research history and state-of-art of interference effects of wind loads of a cluster of tall buildings[J].Journal of Tongji University(Natural Science),2003,3(7):762-766.
[11]Rowan A I,Stoyan S,XIE J M.Tacoma narrows 50 years later-wind engineering investigations for parallel bridges[J].Bridge Structures:Assessment Design and Construction,2015,2(1):3-17.
[12]BAI Hua,LI Defeng.A study on improving measures for wind-resistance stability of pedestrian suspension bridge[J].Highway,2012,1(12):22-25.
[13]Rowan A I,Stoyan S,XIE J M.Tacoma narrows 50 years later-wind engineering investigations for parallel bridges[J].Bridge Structures:Assessment Design and Construction,2014,3(1):3-17.
[14]Michael C H H,Larsen A.Aerodynamic investigations for the deck of stonecutters bridge emphasizing Reynolds number effects[M].Busan Korea:Elsevier Plublication,2012:649-656.
[15]刘小兵,刘志文,陈政清.双幅桥面桥梁主梁断面的气动选型[J].振动与冲击,2009,28(8):34-37.LIU Xiaobing,LIU Zhiwen,CHEN Zhengqing.Aerodynamic optimization of twin deck bridge girder’s cross section[J].Journal of Vibration and Shock,2009,28(8):34-37.