钢桥塔与塔吊联合体系抖振响应试验研究

研究了自立状态钢桥塔与塔吊组成的联合体系的抖振性能及塔吊对钢桥塔抖振响应的影响.通过钢桥塔与塔吊共同作用的联合气弹模型风洞试验与自立状态桥塔气弹模型风洞试验,识别出了两种体系的模态参数并获得了不同风速及不同风偏角下两种体系的抖振响应,对风速与风偏角的影响规律进行了总结与比较,对比研究了联合体系中塔吊与桥塔在顺桥向、横桥向的振动响应差异.结果表明,钢桥塔与塔吊的风致抖振位移响应均值可以近似表示为风速的二次函数,位移响应均方差则表现出一定的波动性,塔吊会显著减小钢桥塔抖振位移响应的均值与均方差,钢桥塔与塔吊风致抖振响应存在明显的风偏角效应,塔吊的局部振动效应使得顺桥向塔吊位移相对桥塔位移存在明显的放大效应,而横桥向存在一定的缩小效应.

Experimental Study of Buffeting Response for Joint System of Steel Pylon and Tower Crane

In order to clarify the buffeting performance of the joint system composed of free-standing steel pylon and tower crane as well as the effect of tower crane on the buffeting response of steel pylon, wind tunnel tests of aeroelastic model of the joint system and free-standing pylon are designed and carried out. Modal parameters and buffeting performance under different wind speeds and wind yaw angles of the two systems are obtained. The effects of wind speed and wind yaw angle on the two systems are summaried and compared, and the vibration responses of the joint system between tower crane and steel pylon in both longitudinal direction and lateral direction are compared in the end. The results show that the mean value of wind-induced buffeting displacement of steel pylon and tower crane can be approximately treated as a quadratic function of wind speed, while the standard deviation of displacement oscillates back and forth with the increase of wind speeds, and the existence of tower crane can decrease the mean value and standard deviation of wind-induced buffeting displacement of steel pylon significantly. Wind yaw angle has obvious effects on the wind-induced response of steel pylon and tower crane. The vibration response of the tower crane is much larger than that of pylon in longitudinal direction of bridge, but it is a little smaller in lateral direction due to the local vibration of tower crane.