Monitoring the effects of impact damages on modal parameters in carbon fiber entangled sandwich beams

Amir Shahdin (1) , Laurent Mezeix (2) , Christophe Bouvet (3) , Joseph Morlier (1) , Yves Gourinat (1)

1 ICA - Institut Clément Ader
2 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
3 LGMT - Laboratoire de Génie Mécanique de Toulouse

The aim is to study the impact toughness of two types of entangled sandwich materials (heavy and light) with the help of vibration testing. A simple case of symmetrical impacts is studied in this article as no literature is available regarding impact tests on entangled sandwich materials. The variation of modal parameters with two levels of damage (BVID and Damage not apparent on the surface) is studied. Vibration test results show that the light entangled specimens possessing good damping capabilities seem more sensitive to impact damage than the heavy ones. Furthermore, damping is found to be more sensitive to damage than the stiffness variations, so it is reasonable to assume that damping may be used instead of natural frequency as a damage indicator tool for structural health monitoring purposes.

Mots clés: Entangled sandwich materials; Vibration testing; Impact testing; Modal parameters

Domaines: Mécanique des matériaux [physics.class-ph]

Amir Shahdin, Laurent Mezeix, Christophe Bouvet, Joseph Morlier, Yves Gourinat. Monitoring the effects of impact damages on modal parameters in carbon fiber entangled sandwich beams. Engineering Structures, 2009, 31 (12), pp.2833-2841. ⟨10.1016/j.engstruct.2009.07.008⟩. ⟨hal-01851905⟩