Steel stiffened panels are widely used in engineering design and construction. However, numerical modeling and analysis effort for a three-dimensional (3D) stiffened panel may be notable, especially for the ultimate limit state of ship structures. Therefore, a homogenization method is outlined that transforms 3D stiffened panel into an Equivalent Single Layer (ESL) concerning the same mechanical behavior. ESL stiffnesses are obtained with a unit cell analyses based on stiffened panel where periodicity is imposed with boundary conditions based on a first-order shear deformation theory (FSDT). Stiffnesses were determined from the first derivative of a membrane force and bending moment obtained with numerical simulations. The effect of initial imperfection shape was included in the analysis to account for local and global buckling behavior. ESL with non-linear stiffness was implemented in Abaqus UGENS subroutine, allowing incremental evaluation of stiffness. Ultimate strength prediction of a steel grillage model with ESL finite element analysis was in excellent agreement with detailed 3D FEM analysis. The key in this analysis was consideration of non-linear ESL stiffness as linear analysis was unable to detect the point where ultimate strength capacity of the grillage was reached.

钢加强板广泛用于工程设计和施工。但是，对于三维（3D）加劲板的数值建模和分析工作可能会值得注意，特别是对于船舶结构的极限状态。因此，概述了一种均质化方法，该方法可将3D刚性面板转换为涉及相同机械行为的等效单层（ESL）。ESL刚度通过基于加劲板的晶胞分析获得，其中基于一阶剪切变形理论（FSDT）在边界条件下施加周期性。由通过数值模拟获得的膜力和弯矩的一阶导数确定刚度。分析中包括初始缺陷形状的影响，以说明局部和整体屈曲行为。在Abaqus UGENS子例程中实现了具有非线性刚度的ESL，从而可以逐步评估刚度。使用ESL有限元分析的钢制格栅模型的极限强度预测与详细的3D FEM分析非常吻合。该分析的关键是考虑非线性ESL刚度，因为线性分析无法检测出达到格栅极限强度的点。