An original pure bending device with large displacements and rotations for static and fatigue tests of composite structures

Abstract

As composite structures, flexible structures have, for pure bending loading, significant displacements and rotations. The design and the dimensioning of these structures require good material characterization beyond the small deformations domain. This paper thus proposes a new original device making pure bending loading possible in large transformations. The sample is embedded at each end using a sleeve with a rigid body movement. The applied bending moment is perfectly controlled during the loading. A behavior model of the bench based on the beam theory for large transformations is developed, making it possible to dimension and design this bench. An experimental campaign using glass/epoxy composite samples has validated this new device in static and fatigue states. This device was used for identification of a fatigue model dedicated to flexible composite structures.