考虑剪力铰与钢弹簧变刚度下浮置板轨道减振特性研究
Damping Characteristics of Floating Slab Track Considering the Existence of Shear Hinge and Stiffness Change of Steel Spring
黄腾锋 1万灵 2黄强 3张雨萱 1崔正阳1
作者信息
- 1. 宁波大学 土木工程与地理环境学院, 浙江 宁波 315211
- 2. 江西省交通科学研究院, 南昌 330200;浙江大学 建筑工程学院, 杭州 310058
- 3. 宁波大学 土木工程与地理环境学院, 浙江 宁波 315211;宁波大学 滨海城市轨道交通协同创新中心, 浙江 宁波 315211
- 折叠
摘要
针对浮置板轨道中浮置板端部位移偏大的问题,研究剪力铰设置与钢弹簧变刚度两种方式对浮置轨道位移的改善效果.将剪力铰简化为剪切弹簧阻尼单元,根据浮置板挠度分布及钢弹簧间距调整浮置板下钢弹簧刚度,基于振型叠加法和龙格-库塔法数值计算研究不同剪力铰刚度与钢弹簧刚度下浮置板轨道的减振特性.研究表明,设置剪力铰可以有效减少浮置板端部的位移差,但主要对端部3m左右范围内的浮置板位移改善较为有效,剪力铰刚度并非越大越好,刚度取值应使浮置板和钢轨的位移波动幅度尽可能小.在钢弹簧总刚度不变的前提下,根据浮置板挠度分布调节钢弹簧刚度对浮置板位移和端部位移差的改善效果不大,但可以有效减少钢轨位移及其波动幅度,且长型浮置板轨道下的减振效果更好.适当扩大钢弹簧间距从而增大弹簧刚度可以改善浮置板轨道的位移响应,但间距过大时浮置板位移会出现剧烈波动.研究可为浮置板轨道的减振设计提供一定参考.
Abstract
Concerning the relatively large displacement at the end of a floating slab,the displacement improvement effect to the floating slab track by setting shear hinge and changing the steel spring's stiffness is studied.The shear hinge is simplified as shear spring/damping element,the steel spring's stiffness under the floating slab is adjusted according to the deflection distribution of the floating slab and spacing of the steel spring.Then the vibration attenuation characteristics of the floating slab track is analyzed based on modal superposition method and Runger-Kutta numerical calculation.The research indicates that the shear hinge is effective to reduce the displacement discrepancy at the end of the floating slab,but it is effective to improve the floating slab's displacement mainly in the area about 3 m away from the ends.It is not rational to set the stiffness value of the shear hinge as much as possible,instead,the value should be so determined that the displacement fluctuation of the floating slab and rail is as weak as possible.Under the conditional that the total stiffness of the steel spring keeps unchanged,the displacement improvement of the floating slab and displacement discrepancy at the end is essentially independent of adjusting the steel spring's stiffness according to the deflection distribution of the floating slab.However,the adjustment of the spring stiffness can effectively decrease the displacement magnitude and fluctuation of the rail,and make the damping effect much better for a longer floating slab.Appropriate increase of the steel spring's stiffness by increasing the steel spring's spacing is valid to improve the displacement response of the floating slab track,however,the displacement response will be violent if the steel spring's spacing is overlarge.The presented study may provide a guidance for the vibration attenuation design of the floating slab tracks.
关键词
振动与波/浮置板轨道/剪力铰/钢弹簧刚度/端部位移差/钢轨位移/浮置板位移Key words
vibration and wave/floating slab track/shear hinge/steel spring' s stiffness/end displacement discrepancy/rail displacement/floating slab displacement引用本文复制引用
基金项目
国家自然科学基金(52008214)
宁波大学滨海城市轨道交通协同创新中心开放基金(2020003)
江西省交通厅重点科技项目(2020Z003)
宁波市自然科学基金(2023J083)
出版年
2024
国家科技期刊平台
NSTL
万方数据