重力对热镀锌带钢固有频率的影响

he influence of gravitational force on the natural frequency of strip steel is studied. The three dimensional nonlinear dynamical equations of strip steel are formulated by Hamiltonian principle. And the influences of gravitational force, size and initial tension on strip steel are considered during the deduction. As a result, the influence of gravitational force on longitudinal frequency is negligible, and it is degressive on transverse frequency of strip steel as bending rigidity is increased. As the order of modal increasing，the influence of gravitational force on the in-plane transverse frequency is weaken, but the influence of gravitational force on the out-of-plane transverse frequency is almost constant. The influence of gravitational force is degressive on transverse frequency of strip steel as initial tension is increased, but it is opposite side as the thickness of strip steel is increased. Hence, the influence of gravitational force is not negligible for the heavy thickness or the low tension of strip steel.