Diagnosis of wooden beams: an application of ultrasonic techniques

This paper presents an application of the ultrasonic technique to the analysis of wooden beams by using a testing device developed for concrete, with the aim of evaluating the effectiveness of this technique to study the density distribution and to detect defects and damaged areas, in order to assess the health state of the structural elements. Three different timber beams have been tested, made by glue-laminated wood, plain wood and old wood, respectively. Ultrasonic NDT allowed to detect in-homogeneity and defects as differences between layers in glue-laminated timber beams, shrinkage splits, knots and deteriorated areas in plain wood beams and areas affected by biotic attack in old wood beams.