移动荷载列作用下简支梁振动响应参数研究

发布时间：2019-01-27 07:13

【摘要】：推导了移动荷载列作用下简支梁位移响应的精确解,在此基础上引入3个无量纲参数,研究了荷载移动速度、荷载频率及结构阻尼对桥梁响应的影响,分析了简支梁在一定荷载速度下的共振和消振现象发生机理。结果表明:桥梁跨中的最大位移响应并非随着荷载速度的增大而单调地增大,而是表现出一种类似正弦但波幅逐渐变大的方式;当移动荷载列以消振速度通过桥梁时,引起的桥梁余振响应趋近于零;简支梁的共振速度与移动荷载列的间距有直接关系,当共振速度同时又是消振速度时,共振现象被抑制;当简谐荷载移动速度较低时,梁体位移在荷载频率等于梁体第一阶自振频率时达到最大响应,随着荷载移动速度的增大,梁体位移达最大响应不再发生于荷载频率等于梁体第一阶自振频率的情况。
[Abstract]:The exact solution of displacement response of simply supported beam under moving load sequence is derived. On this basis, three dimensionless parameters are introduced, and the effects of load moving speed, load frequency and structural damping on bridge response are studied. The mechanism of resonance and vibration attenuation of simply supported beam under certain load velocity is analyzed. The results show that the maximum displacement response in the span of the bridge does not increase monotonously with the increase of the load velocity, but shows a similar sinusoidal but gradually increasing amplitude. When the moving load sequence passes through the bridge at the damping speed, the bridge Yu Zhen response will approach zero, the resonance velocity of the simply supported beam is directly related to the distance between the moving load series, and the resonance phenomenon is suppressed when the resonance velocity is at the same time the damping velocity. When the moving speed of simple harmonic load is low, the displacement of beam reaches the maximum response when the load frequency is equal to the first natural frequency of beam, and with the increase of load moving velocity, When the load frequency is equal to the first order natural vibration frequency of the beam, the maximum displacement response of the beam no longer occurs.
【作者单位】：北京交通大学土木建筑工程学院;
【基金】：国家973项目(2013CB036203) 国家自然科学基金资助项目(51178025,51108023) 中央高校基本科研业务费专项资金资助项目(C11JB00040)
【分类号】：U441.3

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