Dynamic characteristic of steel tubular members connected with typical joints of a transmission tower

Breeze vibration often occurs in steel tubular members of a transmission tower. Critical wind speed for vibration starting is related to natural frequencies of steel tubular members. To analyze the law of their natural frequencies, the 1st natural frequencies of steel tubular members were obtained connected with typical joints in different slenderness ratios through dynamic characteristic tests and ANSYS simulations. The results showed that the 1st natural frequencies in weak axis with I-inserting-plate joint and U-inserting-plate joint were close to those with hinge joints at both ends and their 1st natural frequencies in strong axis were close to those with fixed joints at both ends; the 1st natural frequencies of steel tubular members connected with cross-gusset joints and flange joints were close to those connected with hinge joints at both ends and bolt number had little effect. Finally, a simplified calculation method of the 1st natural frequencies was deduced for designing conveniently.