基于现场实测的拉线式测风塔风致振动响应及模态特性研究OA

This study investigates the dynamic characteristics and their variation with vibration amplitude of a 110-meter-high guyed anemometer tower through integrated theoretical analysis and field measurements.Field dynamic tests were conducted to evaluate the dynamic behavior of the stay cables and determine the cable ten-sions.A finite element model of the tower was developed incorporating the measured cable forces,and the modal properties of the structure were analytically evaluated.A monitoring system was established to record structural dynamic response and wind conditions,enabling identification of the modal parameters.The results demonstrate that:Cable tension significantly influences the modal properties,with measured tensions in cables at the same height varying by up to 40%,underscoring the importance of accurate tension measurement for pre-cise modeling;The wind-induced vibration response exhibits notable multi-modal participation,and the mea-sured natural frequencies show less than 3.5%discrepancy from the finite element predictions with good agree-ment in mode shapes;Under low-amplitude vibrations,the first three natural frequencies and damping ratios in two orthogonal directions vary only slightly with the root-mean-square of acceleration response,while the modal damping ratio decreases with increasing mode order.