摘要
基于Davenport谱,利用线性滤波法对30、50 m跨度单层索系、纵向双层抗风索系和纵横向双层抗风索系柔性支架进行了风振响应及风振系数取值分析,通过改变跨度和支架高度,得到大跨度柔性支架的位移、索拉力风振响应规律,并计算出结构的位移风振系数,并给出建议取值。研究结果表明:钢支架高度对于悬索结构整体自振频率和自振周期影响较小,悬索跨度和初始预应力大小对结构动力特性即自振频率和自振周期有较大影响;双层索系的风振索拉力整体小于单层索系,弥补了柔性支架负风向刚度小的缺点;单层索系柔性支架在脉动风作用下,其跨中挠度超过索跨度的1/50,双层索系明显减小了索跨中风振位移,可根据实际需要选用该结构形式;根据结构形式的不同,跨度为30 m的柔性光伏支架正风向风振系数建议取为2.621~2.673,负风向风振系数建议取为2.371~2.709;跨度为50 m的柔性光伏支架正风向风振系数建议取为2.558~3.048,负风向风振系数建议取为2.385~3.030。
Based on the Davenport spectrum,the AR method is used to analyze the wind vibration response and wind vibration coefficient values of large-span single-layer cable system,longitudinal double-layer wind resistant cable system,and longitudinal and transverse double-layer wind resistant cable system flexible supports.By changing the span and support height,the displacement and tension wind vibration response laws of large-span flexible supports were obtained,and the displacement wind vibration coefficient of the structure is calculated,and recommended values are given.The research results indicate that the height of the steel support has a relatively small impact on the overall natural frequency and period of the suspension structure,while the span of the suspension and the initial prestress have a significant impact on the dynamic characteristics of the structure,namely the natural frequency and period.The wind induced tension of the double layer cable system is generally smaller than that of the single layer cable system,which compensates for the small negative wind stiffness of the flexible support.Under the action of pulsating wind,the mid span deflection of a single-layer cable flexible support exceeds 1/50 of the cable span.The double-layer cable system significantly reduces the wind induced displacement of the cable span,and this structural form can be selected according to actual needs.According to the different structural forms,the recommended positive wind vibration coefficient for flexible photovoltaic brackets with a span of 30 m is 2.621-2.673,and the recommended negative wind vibration coefficient is 2.371-2.709.The recommended positive wind vibration coefficient for flexible photovoltaic brackets with a span of 50 m is 2.558-3.048,and the recommended negative wind vibration coefficient is 2.385-3.030.
作者
刘瑞峰
陈静
王子庠
张振昌
LIU RuifengCHEN Jing;WANG Zixiang;ZHANG Zhenchang(North China Power Engineering Co.,Ltd.,China Power Engineering Consulting Group,Beijing 100120,China)
出处
《武汉大学学报(工学版)》
CSCD
北大核心
2024年第S1期41-49,共9页
Engineering Journal of Wuhan University
关键词
柔性光伏支架
大跨度
风振响应
风振系数
DAVENPORT谱
flexible photovoltaic brackets
large span
wind induced vibration response
wind vibration coefficient
Davenport spectrum
