Advanced Failure Modelling of Thin-Walled Steel Structures at Sea

Ships and offshore structures are sometimes subjected to accidental situations which compromise their structural integrity and put into question their ability to keep functioning. Examples for those situations include collision, grounding, raking, attacks on naval ships and offshore blast walls exposed to an accidental explosion among others. In order to accurately assess their safety at sea, it is necessary to evaluate and model the failure behavior of thin walled steel structures. This modeling must be done in a way that guarantees a realistic amount of engineering and computational effort. Through modelling cracks within finite elements, XFEM (eXtended Finite Element Method) of shell elements will meet the balance between cost and accuracy, but it requires considerable development before it’s ready for engineering practice.

The aim of this project is to make XFEM more practical through relating its modeling and input to material properties a priori rather than through structural and experimental level approaches currently used a posteriori. The TSL (Traction Separation Law) needed for XFEM will be developed based on physical modelling to account for many different and increasingly complex loading scenarios. This will culminate into demonstrating that a structurally representative dynamic test can be predicted with an XFEM simulation based on material level data. This development will lead to the possible application of XFEM in engineering practice, thus making it available to the Dutch maritime and offshore industry with reasonable cost.