Tensile shear tests of bonded joints using digital image correlation
Sandwich structures offer very high lightweight design potential due to their very high specific stiffness and are therefore used in many aerospace structures. A key challenge in the design of sandwich components is the load transfer of local forces that occur at the joints to the sandwich. The sandwich core, which is usually very soft, and the thin cover skins can only absorb local loads to a very limited extent. Therefore, so-called inserts are used in the load introduction areas, usually simple load introduction structures such as sleeves or bushings that are inserted into the sandwich structure. In application, sandwich components have a large number of connection points, which is why there is a high potential for weight reduction here.
In the BLANCA project, new load introduction structures are being developed using additive manufacturing and optimized structural bonding, which are optimized in terms of the weight and effectiveness of the load introductions. Furthermore, through the further development of virtual and physical testing, the structural verification of corresponding aerospace structures will be made more efficient and robust and, as far as possible, virtualized using validated and verified simulation models. To this end, analytical and numerical methods for modeling and simulating material and structural behavior under structural load are being developed and validated via a sample and test program. In addition to reducing costs in the course of component development, this also succeeds in saving valuable resources, since a smaller number of physical tests are necessary as part of the validation.
