Wang Zheng-zhong

Reliability and Sensitivity Analysis of Dendriform Structure

Reliability, sensitivity and correlation of dendriform structure are deeply investigated, respectively. Firstly, reliability of dendriform structures is carried out. Members in the dendriform structures are classified into four types according to their layouts. Wall thickness, external radius, Youngs Modulus of members and vertical load are defined as random variables, respectively. Four kinds of performance functions, e.g., maximal nodal deflection, maximal stress, natural frequency and buckling eigenvalue, are taken into consideration. Secondly, sensitivity of above-mentioned four performance functions was presented to identify the effect of different kinds of random variables and different positions of members. Finally, correlations among performance functions are investigated. Numerical results can provide a reference for the design of dendriform structure.

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.