An Investigation of the Fracture of Butt Joints in Parallel-Laminated Veneer
Keywords:Parallel-laminated veneer, butt joints, fracture mechanics, joint spacing
AbstractA finite-element analysis and experimental testing program was conducted to investigate the fracture mechanics aspects of butt joints in parallel-laminated veneer (PLV). The effects of the number of plies, ply thickness, and joint spacing were investigated. It was found that the isotropic and orthotropic solutions for edge-cracked specimens were very close. Also, the increase in the stress-intensity factor for the exterior butt joint was of the order of only 4% for a joint separation spacing of four ply-thicknesses. In general, it was found that Mode I fracture toughness increased with decreasing veneer thickness and that the fracture toughness of exterior butt-jointed specimens varied with veneer thickness and number of plies. Results of the butt-joint interaction tests indicate a much higher degree of joint interaction than predicted by the finite-element analysis.
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