Estimation of load-carrying capacity for thin-walled composite beams

The paper deals with thin-walled channel section beams made of composite laminates (epoxy resins reinforced with unidirectional long fibres). Two types of laminates have been analysed: carbon fibre reinforced polymer (CFRP) and E-glass fibre reinforced polymer. Thin-walled channel section beams subjected to pure bending in plane with the lowest second moment of area have been taken into consideration. Numerical and experimental investigations of columns loaded till failure have been performed. Also, models at the atomic level for analysing interactions between fibres and an epoxy resin have been prepared, and the obtained results have been correlated with a structural analysis of damaged beams. A comparison of the experimental results with the results of numerical simulations and the structural test results leads to a conclusion that tests allow one to predict the manner in which composite laminates are destroyed not only at the macro or micro, but also at atomic level. The above-mentioned experimental study permits the development of methods for estimating the ultimate load using numerical simulations.