FPSO甲板开孔板架孔边的应力集中优化

Stress Concentration Optimization for the Opening Edges of FPSO Deck Grillage Frame

应力集中现象在船舶等大型海洋结构物中非常普遍,为减小应力集中系数,避免因应力集中而产生疲劳裂纹等破坏,需在船舶结构设计中对开孔区域的应力集中进行校核并设置加强方案。以某一浮式生产储油卸油装置(Floating Production Storage and Offloading,FPSO)工程项目中艏楼甲板上的开孔板架为例,提出几种可行的加强方案;利用有限元分析软件对各优化方案孔边的应力集中系数进行计算,并分析不同方案对应力集中系数的优化效果。通过计算和优化得到符合设计要求的应力集中加强方式,分析结果表明,采用复合加强方式能大幅度降低开孔处的应力集中。

Stress concentration is very common in large marine structures including ships.To reduce the stress concentration and to avoid fatigue crack damage caused by stress concentration,it is necessary to check the stress concentration factor and to provide reinforcement to the opening regions in the ship structural design.This study produces several feasible reinforcement schemes with the perforated bow deck grillage frame of a FPSO(Floating Production Storage and Offloading)as the object.The finite element analysis software is used to calculate the stress concentration factors at the opening edges of the optimized schemes,and the effect of different optimization schemes on the stress concentration is analyzed.Thus the stress concentration reinforcement scheme satisfying the design requirements is obtained by calculations and optimization.The analysis result shows that the stress concentration at the opening can be significantly reduced by the composite strengthening method.