Influence of boundary conditions on the critical and failure load in the GFPR channel cross-section columns subjected to compression

摘要

This paper deals with experimental investigation of thin-walled GFRP laminate columns with channel cross-section subjected to compression. The specimens were C-shaped columns with length of 1 = 250 mm and following cross-section dimensions (width × height × thickness of the wall): 82 × 40 × 2.08 mm. All specimens were made of glass-epoxy unidirectional prepreg tape (GFPR). Each column was made as 8-ply laminate where the layers were arranged at various angles and they are as follow: [0/90/0/90/90/0/90/0] - further denoted as C1, [90/-45/45/0/0/45/-45/90]-C4 and [45/-45/45/-45/-45/45/-45/45] - C5. The aim was to investigate influence of boundary conditions on the critical and failure load. On the basis of the results, the critical values of loads were determined using the following methods: ? the P-w~2 method, ? the P-(ε_1-ε_2) curve inflection point method.