Experimental validation of the mechanical coupling response for hygro-thermally curvature-stable laminated composite materials

Stacking sequence configurations for hygro-thermally curvature-stable (HTCS) laminates have recently been identified in 9 classes of coupled laminate with standard ply angle orientations +45, "1245, 0 and 9

Experimental validation of design concepts for laminated composite materials with thermal and/or mechanical coupling response

New and important experimental observations are presented, revealing that cylindrical room-temperature shapes are present in a broader range of coupled laminate classes than previously observed, and that contrary to current understanding, at least one class of coupled laminate developed into a saddle shape at a relatively high side-length-to-thickness ratio. Bistable and Pseudo-Bistable Snap-through behaviour are also observed in a large proportion of the 24 classes of coupled laminate. Pseudo-Bistable behaviour implies that a snap-though may be invoked, but that a force must be continuously applied to prevent snap-back; this behaviour has not been characterised previously in the literature. Hygro-thermally curvature-stable laminates, identified in 13 of the 24 classes of coupled laminate with standard ply angle orientations, have also been validated experimentally. Such laminates are immune to thermal warping distortions, which has previously made the exploitation of these unique mechanical coupling properties impractical

Résolution parallèle appliquée à des grands systèmes linéaires creux pour le calcul de la matrice de souplesse d'une structure mécanique

La résolution de systèmes linéaires creux constitue une base essentielle pour le traitement numérique de nombreux problèmes de calcul scientifique, notamment les problèmes liés aux calculs des structures mécaniques. Ces systèmes, qui apparaissent en particulier dans le cadre de la discrétisation par éléments ou volumes finis, et normalement sont de très grande taille. Les coûts opératoires et en mémoire induits sont tels que le parallélisme est alors une technique incontournable pour résoudre ces très grands systèmes (qui peuvent atteindre dans certains cas plusieurs millions d'inconnues)

Mise au point d'adhesifs hautes performances pour applications en aeronautique, electronique et mecanique

SIGLECNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc