These plots indicate just one of the many forms a structural analysis can take. The basic steps are: modelling of the 3-D form and geometry, description of structure, application of loads, analysis of results, corrective actions, reporting.


3-d model of midship section includes plates, stiffeners, frames, girders


It is usually easiest and best to start by checking the midship area to get a "quick-and-dirty" idea of the structural proposals. The traditional color scales make it easy to identify problem areas relative to each other, and it is then possible to look at particular elements in detail, for example stress levels and possible failure modes.  


Top panels likely to fail due to panel buckling   Individual element stresses in worst-case loading   Top panels likely to fail due to panel buckling   Top panels likely to fail due to panel buckling in another load case


Of course it is possible to separate plate-stiffeners and frames-girders separately in the plots. And again to check first the relative effectiveness of structural members, and then to look at particular elements in detail.


Effect of torsion on longitudinal bulkheads   No limit to the number of loadcases   Hull frames in upper side highly stressed from wave loads   Investigation of superstructure frames


In a relatively complex vessel, there may be many load conditions to consider. These can be checked against each other. But it is a huge simplification from all this data to be able to find out which loadcase and failure mode is critical for a particular element.


Inside slamming load   First efforts at optimising side and superstructure frames   Continued optimisation - stresses in an element   Stresses in an element after optimising