DAMAGE OF GLUED-LAMINATED BEAMS UNDER CYCLIC TORSION

The aim of this paper is to study the behaviour and the lifetime of beams in glued-laminated (GL)

under cyclic torsion. Experimental programmes have been carried out: Periodic triangular

alternate torque with varying amplitude are applied to GL beams with rectangular cross section.

Experimental lifetime is presented by semi logarithmic SL-N curves (SL is torque stress level and

N is failure cycles number). From angular distortion records, we propose a method to obtain the

damage evolution versus time. Duration of load prediction of GL beams under cyclic torque is

approached by a damage theory.