Experimental investigation of pre-damaged thin-walled channel section column subjected to compression

Experimental investigations of channel-section profiles subjected to compression after low-velocity impacts (20 J) leading to global failure are presented. The columns under discussion were made of an eight-layer GFRP laminate with quasi-isotropic, quasi-orthotropic and angle ply arrangements of layers. The profiles were impacted in mid-width of the web or mid-width of the flange in various locations along the profile length. An influence of the impact position and the layer arrangement on buckling and failure phenomena, post-buckling behaviour for impacted and non-impacted columns was thoroughly examined and described. It was found that the local degradation introduced by low-velocity impacts did not affect the global behaviour of the analysed structures to a considerable extent. Moreover, it was noted that the failure mechanism was initiated in the impact location in none of the cases analysed. Additionally, it was stated that a number of fracture points did not have any significant impact on the capacity reduction.