Effective Analysis of Bolted joints in Composites

Purpose and goal

The aim for the project has been to automate the creation of screw joint models (FE) where at least one part is a fibre composite plate. The project also aimed to further develop the failure criteria for NCF (Non-Crimp Fabric) -reinforced composites. The first goal was achieved with the software that was developed by Altair which significantly reduces the time associated with 3D modeling of a screw joint between composites. The second goal was partly achieved. The project was able to pick out the most state of the art failure criteria. However, no room for improvement was found.

Expected results and effects

Speaking for Scania this type of project and the software that was developed for RASK is an enabler to even consider composite structures. Scania is determined to hold its position at the edge of technology and this is right in that area. In order to reach the goal of achieving lighter trucks, mixing of materials is considered to be a fundamental factor. In SAAB:s case better and faster analysis gives them a better opportunity to challenge the competition. The methods developed in RASK will most likely be used in real conditions this spring.

Planned approach and implementation

The project was divided into four work packages (WP). In WP1, KTH and Semcon sought to further develop fracture criteria for NCF-reinforced composites. In WP2, the software company Altair developed a module for its software HyperMesh for automation of screw joints analysis using finite elements (FE). In WP3, Saab, Scania and Linköping university developed appropriate test cases which was used to experimentally verify the work of the WP1 and WP2. WP4 included project management and dissemination.