4.1 An estimate of wood failure is one of the principal means for determining the quality of an adhesively bonded wood joint.
4.2 When evaluated after a water soaking, water soaking and drying, or boiling and drying, the percentage of estimated wood failure is an important criterion for qualifying adhesives for use in plywood, laminated structural timber, adhesively bonded wood products and for daily quality control of the processes for manufacturing various adhesively bonded wood products including but not limited to plywood and laminated timbers. Standards that use the percentage of wood failure are included in Section 2.
4.3 In plywood manufactured from North American softwood species, the percentage of wood failure of Test Method D906 specimens, tested wet after either a vacuum-pressure soak-dry or boil-dry treatment, correlates with the percentage of panels that delaminate in outdoor exposure without protection.7
1.1 This practice provides procedures for estimating the percentage of wood failure that occurs in plywood-shear, block-shear, finger joint test specimens, or any other bondline involving wood.