A group of six glued laminated timber beams was tested in four-point bending until failure. Both standard measuring devices mounted to the beams and digital cameras were employed to provide for a continuous measuring of displacements and strains as well as visualization of damage evolution and subsequently for quantification of damage mechanisms leading to failure of individual beams. This was accompanied by identification of positions of all visible knots and finger joints. It is shown that their distribution plays an important role in the onset of damage evolution and final failure pattern.
