摘要
为研究索梁结构非线性振动过程中拉索的空间运动轨迹及其特性,进行了索梁结构模型试验。测试了索梁结构面内、外几何非线性频率,并和有限元结果对比,两者吻合良好;分别研究了索梁结构在自由振动和强迫振动时,拉索空间运动轨迹的变化过程和规律。研究表明:索梁结构面内固有频率的几何非线性效应明显,频率法测斜拉索索力应以面外固有频率为准;索梁结构在自由振动时,拉索空间振动除幅值呈指数衰减外,还具有"气圈"椭圆形状的长/短轴互换和转动方向的顺/逆时针互换两个特征;在稳态的强迫振动时,拉索空间振动"气圈"形状仅随激励频率的变化而改变。
In order to study the spatial coupling vibration characteristics of cable in cable-beam structure,a cablebeam structure experimental model was carried out. The in-plane and out-of-plane natural frequencies were tested and the results were in good agreement with that of the finite element model. Then,the cable’s space trajectories under free vibration and forced vibration were studied. Research shows that: the in-plane natural frequencies of this cable-beam structure were obviously affected by the geometric nonlinearity. Thus,the out-of-plane natural frequencies should be used for cable tension measurement by frequency method. When the cable-beam vibration was in free vibration,the amplitude of cable spatial vibration was exponentially decayed,with two additional characteristics: i) the interchange on long and short axis of the "balloon"ellipse;ii) the interchange of the rotation direction on clockwise/counter-clockwise. When the cable-beam vibration was in steady state forced vibration,the shape of the "balloon"changed only with the excitation frequency.
作者
孙测世
赵珧冰
SUN Ceshi;ZHAO Yaobing(College of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China;College of Civil Engineering, Huaqiao University Xiamen, Fujian 361021, China)
出处
《地震工程与工程振动》
CSCD
北大核心
2018年第3期127-133,共7页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金项目(11602089)
重庆市教委科学技术研究项目(KJ1600528)
重庆交通大学校内科学基金课题(16JDKJC-A033)
华侨大学中青年教师科研提升资助项目(ZQN-YX505)~~
关键词
索梁结构
拉索
非线性频率
耦合振动
空间运动
cable-beam structure
cable
nonlinear frequency
coupling vibration
spatial motion
