Non-linear buckling analysis of stiffened panels

Abstract

Nonlinear buckling capacity analysis has become a reliable practice in order to investigate the buckling capacities for cases that do not fall into the scope of the traditional standards. DNV has issued the recommended practice DNV-RP-C208 [3] as a guideline for nonlinear finite element buckling analysis. The project aims to apply nonlinear finite element methods to evaluate the buckling capacity of a ship hull stiffened panel under uniaxial in-plane compression load and gravity load. Then, to calibrate and compare the results to conventional codes, this is done by determining the buckling capacity of the panel using "DNV-RP-C201 Buckling Strength of Plated Structures" to establish a capacity benchmark. Then, the finite element analysis program ABAQUS is used to build a stiffened panel model and introduce the material and geometrical nonlinearities using the method outlined in the recommended practice "DNV-RP-C208, Determination of structural capacity by nonlinear finite element analysis methods" to achieve the calibration to the benchmark buckling capacity. The calibration is achieved by studying the effect of two different geometrical imperfection patterns with several different magnitudes. This is used to choose the model with imperfections pattern and magnitude that would provide the buckling capacities closer to the benchmark as a calibrated model. It is then used to study the effect of holes on the buckling capacity of the panel.