静水压力下具有轴对称初始缺陷圆柱壳承载能力研究

摘要

This paper studies the stability load-carrying capacity of cylindrical shells with axisymmetric initial imperfections and local dents. The effects of amplitude, the ratio of radius and thickness, the length of shells and local dents and the position of dents on the critical buckling pressure of cylindrical shells un-der hydrostatic pressure are given out with numerical calculation method. And to reduce the stiffness of cylindrical shells to different amplitudes of the imperfections is made and the relation between the ampli-tudes and coefficient of reduced stiffness is obtained. The results indicate that the essence of the effects of ax-isymmetric initial imperfections on the load-carrying of cylindrical shells is that the imperfections induce the axial bending stiffness reduced and decrease the stability load-carrying of cylindrical shells. Therefore, the stringer stiffener can increase the bending stiffness and improve the load-carrying capacity of cylindrical shells with axisymmetric initial imperfections.%文章针对含有轴对称初始缺陷和局部轴对称凹陷的圆柱壳在静水压力下的稳定承载能力问题进行了研究。通过一种数值计算方法，给出了初始缺陷幅值、壳体半径与厚度比、壳体长度、局部凹陷长度及位置对静水压力下圆柱壳屈曲临界压力的影响。并针对不同缺陷幅值对圆柱壳的刚度进行折减，给出了初始缺陷幅值与刚度折减系数的关系。研究结果表明，对于轴对称初始缺陷对圆柱壳稳定承载能力的影响，本质上是降低圆柱壳轴向弯曲刚度和轴向的薄膜刚度从而造成圆柱壳稳定承载能力的下降，因此针对轴对称初始缺陷可以增加纵筋提高其弯曲刚度，增加稳定承载能力。