某公园外轻柔简支人行桥人致振动响应分析和舒适性研究

Vibration Response Analysis and Comfort Study of a Light and Simply Supported Pedestrain Bridge

我国人行桥正朝着大跨径和纤薄轻巧方向发展,由于我国人行桥设计规范发布时间较早,对于中大跨径的人行桥人致振动控制方面的适用性较差。通过对目前国际上主流的几个人行桥设计规范的比较,得出德国人行桥设计指南EN03(2007)更为适合于中大跨径的人行桥人致振动设计指导。以某已经建成的公园外中等跨径轻柔简支人行桥为例,参考德国EN03(2007)设计指南基于不同行人同步率和人群密度下的2种人群荷载形式,应用直接共振理论,对落入敏感频率范围的横向侧弯振型,通过有限元分析,计算得到2种不同行人动荷载下主梁跨中横向加速度响应时程曲线,对结构的舒适度进行分析,并通过调整支座类型提高结构横向刚度,达到改善桥梁舒适性的目的,为其他人行桥人致振动响应和舒适性研究提供一定的借鉴作用。

The pedcstrain bridge in China is becoming longer in span and lighter in weight. Since the design codes in China were issued too early? the applicability in control of human induced vibration was limited,especially for medium and large span pedestrain bridges. By comparing several current international codes about design of pedestrain bridge, this paper pointed that EN03C2007) is more suitable for the design of human induced vibration in pedestrain bridge with medium and large span. Based on a medium span and simply supported pedestrain bridge outside a park,according to EN03(2007)i two kinds of crowd load forms under different pedestrain synchronization rate and crowd density are referenced, directly resonant theory are applied,and lateral bending mode in sensitive frequency range are analysed,transverse acceleration-time cueves at mid-span of main beams under two defferent pedestrain dynamic loads are calculated. At the same time, the human comfort of structure i.s analysed,and the breaing type are adjusted to improve the lateral stiffness of the structure, which improves the comfort of the bridge. The results provided reference for vibration response and comfort study to other pedestrain bridges.