Abstract：Abstract: Breeze vibration often occur in steel tubular members of transmission tower. Critical wind speed for vibration starting is related to natural frequencies of steel tubular members. To analyze the natural frequency law, 1st natural frequencies of steel tubular members are obtained connecting with typical joints in different slenderness ratio through dynamic characteristic test and ANSYS. The research results account that I-inserting-plate joint and U-inserting-plate joint are close to hinge joint in weak axis and rigid joint in strong axis, 1st natural frequencies of steel tubular members connecting with cross-gusset approximate to connecting with hinge joint and bolt number has little effect. Finally, a simplified calculation method of 1st natural frequencies is deduced to convenient for designing.
2009, Vol. 28 
