Fundamental research on the ultimate compressive strength of ship stiffened plate structures at Arctic and cryogenic temperatures

Research Project, 2019 – 2020

The behavior of stiffened plate structures until and after the ultimate strength is reached is highly nonlinear involving geometric and material nonlinearities. Various types of collapse modes, including overall buckling collapse, beam-column collapse, web buckling induced collapse and flexural-torsional buckling induced collapse, are relevant. Today´s large merchant ship structures are made of different grades of steel materials that should meet specific and challenging requirements for yield strength, ductility, brittleness, etc., in association with operational and environmental conditions.

This project presents fundamental research on the ultimate strength characteristics of ship stiffened plate structures subject to extreme loads and cold temperatures (due to Arctic operation and LNG leakage). Physical model testing on full scale structures will be undertaken at room temperature, Arctic temperature and cryogenic condition. Elastic-plastic large deflection behavior of the test models under axial compressive loads will be measured until and after the ultimate strength is reached. Material properties at Arctic and cryogenic temperatures will be tested in separate material experiments. Nonlinear finite element method models will be developed to compute the ultimate strength behavior. The overall aim is to compare the ultimate strength behavior (structural collapse patterns at different temperatures) between physical model testing and advanced computational modelling.