NUMERICAL AND EXPERIMENTAL STUDY OF THE LATERALTORSIONAL BUCKLING OF GLUED-LAMINATED WOOD BEAMS

Abstract

This paper presents numerical and experimental studies on the structural behaviour of gluedlaminated (‘glulam’) wood beams. The identification of lateral-torsional buckling and the quantification of critical and ultimate loads were first obtained through laboratory tests, whose results were then used to calibrate geometrically nonlinear finite element models. The glulam beams were represented in the mathematical model as a classic elastic-brittle material with orthotropic behaviour, composed of multiple layers of interface elements, capable of transmitting shear and normal stresses, with constitutive laws for the interface elements empirically obtained by testing an instrumented beam. The influence of the grain orientation, the eccentricities of loading, geometrical imperfections (inherent to the manufacturing process of the glulam) and type of the glue material in the nonlinear behaviour of beams of laminated wood will be checked. The experimental and numerical results will be confronted with theoretical stability results, as well as with international codes of practice.

Index Terms - glued-laminated beams; glulam beams; structural stability; numerical and experimental studies.