A composite runout specimen subjected to tension–compression loading conditions: Experimental and global–local finite element analysis

Runout regions in aeronautical structures take place when a stiffener is interrupted due to the presence of significant geometrical conflicts between adjacent areas. At these locations, the load path is substantially modified, and therefore they are identified as one of the most critical regions of an aircraft. The structural design of the regions, in terms of damage tolerance, becomes one of the crucial aspects in the mechanical performance of the whole component, the use of virtual testing techniques playing an important role in optimizing the costs associated to this task. The work developed in this paper deals with the experimental and numerical characterization of the structural performance of a composite runout specimen subjected to uniaxial mechanical actions, specifically to traction–compression loading conditions. Several numerical computations by means of global–local modeling strategies included in the commercial FEA package ABAQUS were accomplished. Particularly, the damage initiation and propagation at the skin–stringer joint around the runout region are explicitly taken into consideration through the use of cohesive interface elements at local level of analysis. The numerical results are compared with the experimental evidences in order to evaluate the level of fidelity and reliability of these simulations.