In composite reinforcement shaping, textile preform undergo biaxial tensile deformation, in plane shear deformation, transverse compaction and outof-plane bending deformations. Bending deformations have been neglected in some simulation codes up to now, but taking into account them would give more accurate simulations of forming especially for stiff and thick textiles. Bending behaviour is specific because the reinforcements are structural parts and out of plane properties cannot be directly deduced from in-plane properties, like for continuous material. Because the standard tests are not adapted for stiff reinforcements with non linear behaviour a new flexometer using optical measurements has been developed to test such reinforcements. This new device enables to carry out a set of cantilever tests with different histories of load. A series of tests has been performed to validate the test method and to show the capacities of the new flexometer to identify non linear non elastic behaviour.

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.

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