摘要
为确定位于高海拔高温差深切峡谷中的大渡河大桥桥址区风特性,采用MFAS型相控阵声雷达风廓线仪和四要素自动气象站对大渡河大桥桥址区的风特性进行了现场实测,分析了桥位处的平均风速、阵风系数、风攻角和风剖面等风特性。研究结果表明:受热力驱动的小尺度局部大风基本每天都存在,但风速不大,桥位处的设计风速仍然受大范围的大气环流控制;桥位处的阵风系数和地表粗糙度系数均比相关规范中常规平原地区的推荐值大;桥面设计高度处的风攻角以负攻角为主,其数值亦比相关规范中常规平原地区的大,风攻角的散布范围和绝对值的大小均随着高度的增加呈现减小的趋势。
In order to determine the wind characteristics at Dadu river bridge in the deep gorge with high altitude and high temperature difference,a field measurement based on MFAS phased array sodar and CAW600-RT automatic-weather-station（AWS）was conducted at the bridge site.The properties of the wind were explored,including the mean wind speed,wind gust factor,wind angle attack,wind profile and so on.The results show that the small-scale strong winds driven by the local thermal disequilibrium occur every day,while their speeds are small.The design of wind speed at the bridge site is still subjected to the general large-scale atmospheric circulation.The wind gust factor and terrain roughness at the bridge site are larger than those suggested in the relevant codes for common flat terrains.Most of the wind attack angles at the height of bridge deck are negative,which are larger than those suggested in the relevant codes for common flat terrains as well.Both the scattered ranges and the absolute values of the wind attack angles display decreasing tendency with the increase of the height.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2015年第3期60-65,共6页
China Journal of Highway and Transport
基金
国家自然科学基金项目(U1334201
90915006)
桥梁结构抗风技术交通行业重点实验室开放基金项目(KLWRTBMC11-01)
关键词
桥梁工程
大跨度桥梁
现场实测
风特性
深切峡谷
风廓线仪
自动气象站
bridge engineering
long-span bridge
field measurement
wind characteristic
deep gorge
wind-profiler system
automatic-weather-station
