Delamination buckling in four-point bending tests. An experimental investigation

A set of carbon-fibre laminated specimens have been subjected to (static) four-point bending tests to assess the conditions for delamination induced by local buckling events of the compressed lamina. Testing conditions prescribed by the ASTM D7264/D7264M-1 standard, valid for monolithic samples, have been followed. It is worth noticing that the delaminated area, which is loaded in compression, at a certain point reaches a critical value and snaps upwards. During the experimental campaign, the applied load and the corresponding displacements have been recorded, as well as the length of the crack and the deformation of the delaminated area by using a Digital Image Correlation (DIC) technique.