Gust Response of a Box Type Stiffening Girder under the Action of Random Wind Force

(1)旋风的主动模拟自然风的模拟是桥面阵风响应风洞研究的一个重要问题。在二维风洞中进行了风场湍流的数值模拟。叶栅的随机伺服控制可以产生任意给定的湍流。(2)用于阵风响应数值处理的气动导纳的风洞模型试验需要通过风洞试验来评估气动导纳。得到了桥梁模型随机响应的时间序列。(3)悬索桥的阵风响应在高达23m/S的大风作用下，现场测量了悬索桥的阵风响应和风速。(4)悬索桥在阵风荷载作用下的安全性考虑风速和风向的概率，计算了运营期间阵风响应引起的应力循环次数和幅值。对桥梁构件在阵风荷载作用下的安全性进行了疲劳破坏校核。

(1) ACTIVE SIMULATION OF TURBULENCESimulation of a natural wind is an important problem for a wind tunnel investigation of gust response of a bridge deck. In the two dimensional wind tunnel simulation of wind turbulence was carried out. The random servo-control of a cascade could produce an arbitrary given turbulence.(2) WIND TUNNEL MODEL TESTS FOR AERODYNAMIC ADMITTANCENumerical treatment of a gust response requires an aerodynamic admittance to be assessed through wind tunnel test. Time series of the random response of bridge models were obtained. Through the time series, random aerodynamic force was analyzed and aerodynamic admittance was obtained.(3) GUST RESPONSE OF SUSPENSION BRIDGEThe gust response of the suspension bridge as well as wind speed was measured at the site in a strong wind up to 23m/s.(4) SAFETY OF A SUSPENSION BRIDGE AGAINST GUST LOADThe amplitude and the number of the stress cycles caused by gust response during the service time were calculated considering the probability of wind speed and direction. Safety of a bridge member against gust load was checked concerning fatigue failure.