Influence of strain rate on fracture behavior of sandwich composite T-joints

Applications of sandwich-structured composites gained increasing interest in aviation and aerospace industries as well as in modern lightweight design. In order to improve the reliability of computational models for the dimensioning of such structures, experimental data are indispensable prerequisites. In the current manuscript, the essential outcomes of experimental and numerical investigations of strain rate effects on the stiffness of honeycomb sandwich T-joints are presented. A series of static and dynamic tensile tests is carried out to understand the influence of different loading conditions on failure and fracture of honeycomb sandwich T-joints within strain rates up to 5000s(-1). A digital image correlation technique was employed to characterize the fracture behavior as well as to verify the strain gauges measurements. Failure modes of adhesively bonded sandwich T-joints are determined by a detailed fractographic analysis. In addition, numerical simulation was performed via three-dimensional finite element models using ABAQUS software, which exhibit excellent agreement with experimental results.