INVESTIGATION OF THE MECHANISM OF FAILURE BEHAVIOUR OF WOOD BASED MATERIALS USING ACOUSTIC EMISSION ANALYSIS AND IMAGE PROCESSING

Abstract

Tensile strength, modulus of elasticity under tension and failure behaviour were ascertained for particleboards, OSB, plywood and MDF with two raw density grades by means of acoustic emission analysis. The strain distribution over the sample surface under load was determined with video image correlation.<BR/>Fracture sites can be predicted relatively well using optical measurements of the deformation under load. A combined observation of narrow and broad surface sides of the specimens is advantageous. Prediction of the cracks is easier for inhomogeneous materials like OSB and plywood than for the more homogeneous materials MDF and particle boards. With the acoustic emission analysis the location of cracks can also be determined to a comparable degree.