轴压复合材料蛋形壳屈曲特性

Buckling of axially compressed composite egg-shaped shells

在对模态缺陷条件下轴压复合材料柱形壳进行屈曲分析的基础上,结合仿生学原理对柱形壳进行形状优化,运用等质量、等容积两种方法,设计与柱形壳开口直径相同的蛋形壳,研究其多模态屈曲特性。结果表明:相对复合材料柱形壳,蛋形壳具有更好的轴向承载能力与更低的缺陷敏感度。从工程实例出发,以单立柱固定式海洋平台的柱形壳桩腿为背景,采用分段式模块化设计的方法,在5%多模态缺陷条件下,研究一般钢结构柱形壳桩腿、碳纤维复合材料柱形壳桩腿、碳纤维复合材料多蛋交接形桩腿的轴压屈曲特性。结果表明:在相同的承载能力下,复合材料多蛋交接形桩腿具有更小的质量、更低的缺陷敏感度与更好的稳定性。

Based on buckling analysis of axially compressed cylindrical shells considering mode imperfec-tions, bionics principle is used to conduct shape optimization on cylindrical shells. Two methods of equal mass and equal volume are used to design egg-shaped shells which have the same aperture diameter with cylindrical shells. Buckling characteristics considering multi-modes imperfections of them are investigated. Results show that composite egg-shaped shells have higher axial load capacity and lower imperfection sen-sitivity than cylindrical shells. According to actual engineering projects, spud legs of single column fixed o-cean platforms are set as background and sectional modularized design method is adopted. Axial buckling characteristics of normal steel cylindrical spud legs, CFRP cylindrical spud legs and CFRP multiple inter-secting egg-shaped spud legs are investigated under five percent multi-modes imperfections. Results show that CFRP multiple intersecting egg-shaped spud legs have lighter mass, lower imperfection sensitivity and better stability with the same load capacity.