特征载荷下海工管状结构屈曲临界载荷分析

圆柱形管状结构在海洋工程领域中应用较多，在进行结构设计时，需重点关注其侧向受载时的屈曲强度问题。通过理论分析和数值模拟，对比研究径向线性载荷变化下圆柱壳的屈曲行为，以经典的Donnell壳体理论为基础，得到圆柱壳的屈曲控制方程，并通过本征值分析方法得到结构屈曲的临界条件。采用有限元软件ABAQUS对线性变化径压下圆柱壳的屈曲进行数值仿真。分析得出径厚比是径向线性分布载荷下圆柱壳屈曲临界载荷的主要影响因素，三角形径压下屈曲临界载荷值约为均布径压下屈曲临界载荷值的2倍。

Analysis on the Critical Buckling Load of Offshore Pipe Structure under Characteristic Load

Cylindrical pipe structure is often used in the offshore engineering, therefore its buckling strength under lateral load should be given more attentions at the structure design stage. Theoretical analysis and numerical simulations should be carried out to study the buckling behavior of the cylindrical shell under different radial linear load. Thus the equation for cylindrical shell buckling control could be obtained on the basis of the classical Donnell shell theory, and the critical structural buckling condition is obtained through eigenvalue analysis. It is concluded that the radius thickness ratio is the major influencing factor of the cylindrical shell buckling under linearly varying load and the critical buckling load under triangular radial loading is twice as large as that under uniform radial loading.