DNV has introduced a method for assessing buckling and ultimate strength limits of stiffened panels following the success of extensive research and development tests at its hydrodynamics and structures division.
Designated the acronym PULS (Panel Ultimate Limit State), the new computerised buckling code is a recognised method for assessing stiffened panels being subjected to the simultaneous action of in-plane loads such as bi-axial compression, tension and shear stresses in combination with lateral pressure.
The PULS code is implemented as a part of the ship newbuilding rules from 2004 and constitutes the basic SiO method for assessing corrosion allowances, the allowable thickness diminution for hull structure. It is also being implemented as part of the Nauticus Ship Hull package for automatic buckling control.
Consisting of advanced mathematical buckling models embedded into simple and user-friendly computer interface for quick strength assessments, the computerised code is available in two different stand-alone user interfaces: the Explorer/GUI and the Excel.
The Explorer/GUI version provides easy access to 3D graphics of different results like buckling modes, redistributed stress patterns, and affords a greater understanding of the physical behaviour of non-linear buckling response, while the Excel interface is fast and convenient to use for automatic buckling control of many real cases. Optimum weight design is also provided using the Excel interface.
The PULS stand-alone software is offered as a package for downloading from DNV Software's home page www2.dnv.com/software/ (under Nauticus/PULS menu). PULS 1.5 version is currently available, and an updated 2.0 version will be released in April.