Design of force introduction onserts for thin-walled fibre-polymer-composites

• Applicant: Professor Dr.-Ing. Helmut Schürmann
• Subject Area: Lightweight Construction, Textile Technology ; Plastics Engineering
• Term: from 2015 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 275176947

Load introduction in fiber-polymer-composites still remains a big challenge for composite designers. Mostly lightweight optimized structures are highly loaded; an additional problem is that composites always are applicated to thin structures, predominantly two-dimensional structures, such as sheets and shells. Load applications, in particular in the third dimension, often pose a special problem, since in this direction only the much weaker transverse tensile strength of the laminate is available. Since the strength in this direction is less than the longitudinal properties used in FRP, force introduction points have to be considered much more deeply.At the institute of Konstruktiver Leichtbau und Bauweisen a wide range of force introduction methods have been developed and tested. This includes the problem of the point loading on thin laminates. However, previous studies were limited mainly to metallic studs that were integrally embedded in the laminate. The design method worked out can directly be used by design engineers.However the material combination of FRP - metal represents an unfavorable material combination. Therefore, within the framework of this research project the application of force introduction shall be implemented in a FRP design.From that three main research tasks arise: the connection of the force introduction element to the basic structure, the integration of a thread and the optimal integration of a function like a universal joint.The overall objective is to give to the composite engineers design recommendations and the necessary reliable data in order to reach a lightweight optimum with maximum transmittable forces.

• DFG Programme: Research Grants