Improved calculation model of dynamic stability of main framework of radial gate

Dynamic instability of the arm is one of the main reasons for the failure of radial steel gate, and it is the theoretical problem for design. An improved calculation model of dynamic stability of the arm is proposed according to forced characteristic of main framework and dynamic stability theory. Combining with an engineering example, this paper discusses conditions and characteristics of parametric resonance of the arm, i.e., the amplitude of dynamic load which causes parametric resonance becomes smaller when exciting frequency is closer to natural vibration frequency of the arm. The improved calculation model provides information for the study of dynamic stability of radial gate.