Bending test of composite reinforcements

In shaping of composite reinforcements, tensile stresses are the major stresses, while in plane shear strains are the major strains. However the knowledge of the bending behaviour would give more precisely simulation of forming especially for stiffer and thicker textiles. Two standard tests are used to determine it. The cantilever test is limited because of its elastic linear model. The KES fabric bending test allows a more complicated model but its use is difficult for stiff and thick reinforcements. A new cantilever test using optical measurement has been developed to provide the searched flexibility. Tests have been performed on a carbon woven reinforcement and compared with KES measurements. The results allow to validate the experimentation.