Elastic tripping analysis of corroded flat-bar stiffeners
DOI:
https://doi.org/10.15276/opu.3.50.2016.04Keywords:
corroded steel plate, tripping, FEM, rough surfaceAbstract
Tripping of stiffeners is one of the buckling modes of stiffened panel which could rapidly lead to its catastrophic failure. Loss of thickness in web and flange due to corrosion reduces elastic buckling strength of stiffeners. It is common practice to assume a uniform thickness reduction for general corrosion. Since the real corroded plate has rough surfaces, to estimate the remaining strength of corroded structures, typically a much higher level of accuracy is required. There is a little study on strength analysis of corroded plates with rough surface especially as a function of corrosion degrees. The aim of present work is to analyze elastic tripping stress of flat bar stiffeners with both-sided corroded surfaces. Undulated surfaces are generated based on the power spectrum of the corroded surface. Elastic tripping stress is calculated using ANSYS code. Finite elements method is employed to analyze elastic tripping stress of corroded steel flat bars with both sided rough surfaces. Comparing the results with elastic tripping strength of corroded flat bars with uniform thickness, a reduction factor is proposed. It is found that reduction factor of buckling strength by uniform thickness assumption is overestimated.
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