Investigation on the behaviour of fully thermoplastic composite sandwich beams under concentrated loads

The recent development of new low cost manufacturing processes adopting thermoplastic matrices in the production of structural long fibre reinforced laminates is fostering an increasing interest towards this class of materials. The automotive sector in particular is attracted by the high energy absorbing, damage tolerance performances and manufacturing and recycling potentials of structural thermoplastic composites. In this study a number of fully thermoplastic sandwich beams have been manufactured in order to investigate flexural and shear rigidity performances as well as the indentation behavior under static concentrated loads.

ANALISI DEL COMPORTAMENTO AD INDENTAZIONE IN TRAVI SANDWICH IN COMPOSITO CON ANIMA IN SCHIUMA POLIMERICA

Nel presente lavoro si propone una estensione dei modelli basati sulla teoria delle travi vincolate su una fondazione cedevole di tipo Winkler per lo studio del comportamento ad indentazione di travi sandwich in schiuma polimerica sollecitate da carichi concentrati. L’approccio proposto è in grado di considerare schiume polimeriche aventi comportamento a compressione di tipo non lineare. Sono derivate soluzioni analitiche in forma chiusa della curva di indentazione per anime in schiuma polimerica il cui comportamento a compressione è approssimabile con un andamento bi-lineare. In tal modo è possibile considerare comportamenti di softening o hardening della schiuma nel tratto post-elastico. …

Indentation of rigidly supported sandwich beams with foam cores exhibiting non-linear compressive behaviour.

A generalized analytical approach to investigate the indentation of sandwich beams under concentrated loads is presented, based on the Winkler foundation theory. A segment-wise model is implemented to the case of fully backed sandwich beams with polymeric foam cores exhibiting generic non-linear compressive behaviours. Closed-form analytical solutions of the indentation curve are obtained for simplified foam compression behaviours: elastic-perfectly-plastic, bilinear and bilinear-perfectly-plastic. Analytical predictions are compared with experimental data from sandwiches employing foam cores with peculiar non-linear behaviours. The proposed models are found to give a better match of the e…

INVESTIGATION OF THE INDENTATION BEHAVIOUR OF FOAM CORED LIGHTWEIGHT COMPOSITE SANDWICHES