Crashworthiness is a fast growing branch of engineering science and plays a major part in the practical design of vehicles. SINTEF has developed extensive expertise in the field of structural crashworthiness by use of the finite element method and access to laboratory recourses. The work is carried out in close collaboration with SIMLab, NTNU. 

Crashworthiness can be considered as composed of three basic disciplines: materials engineering and design, combustion and fire and finally medical engineering (biomechanics). The industrial interests cover civil, automotive, marine, military and aerospace oriented applications, where the automotive sector is probably the most prominent discipline in this respect. The annual number of fatalities related to traffic accidents in the OECD countries exceeds 40000 and amounts to an annual reduction of the GNP of 1-2%. It comes as no surprise that the automotive sector and its sub suppliers continuously strive for more crashworthy designs in their products.

Structural crashworthiness concerns absorption of kinetic energy by considering designs and materials suitable for controlled and predictive energy absorption. In this process, the kinetic energy of the colliding bodies is partly converted into internal work of the bodies involved in the crash. Crash events are usually highly non-linear and may involve material failure, global and local structural instabilities and failure of joints. Also, strain-rate and inertia effects may play an important role in the response of the structures involved.

The finite element method is widely used for design of crashworthy structures. Still, the need for enhanced prediction accuracy and robust numerical models to cope with complex phenomena such as material failure and failure of local joints are evident. For some components, the crash simulation will not be done directly, but initialized after a forming/process simulation of the part. This will ensure that the history effects in the material are taken into account in the crash simulation. On the other hand, use of new and sophisticated materials may need extensive testing and development of new numerical material models. SINTEF’s knowledge of material behavior, efficient implementation in computer codes and element technology are cornerstones in order to reach the goals of simulation robustness and enhanced prediction accuracy of dynamically loaded structural components. In order to evaluate the performance of newly developed models, SINTEF has access to a well equipped laboratory where quasi-static and dynamic tests can be carried out on material, component and system level.

• The following applications are of relevance:
• Process-based crash analysis of Hydro Aluminium bumper system (OGL/TB)
• Finite element simulations of self-piercing riveting (AGH/RP)
• Strain-rate testing using SHTB (AC)
• Crashworthy design of cast magnesium/aluminium components (CD/OGL)
• Improved prediction of inelastic deformation and fracture (OGL)
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