Gluability of out-of-service utility poles
This investigation determined the gluability of weathered, out-of-service southern yellow pine (SYP) (Pinus spp.) utility poles. Three types of adhesives were used: resorcinol-phenol formaldehyde (RPF), polyvinyl acetate (PVA), and casein. The poles consisted of two service duration groups: 5 and 25 years. Longer weathering caused greater reduction in creosote content, especially in the outer andupperportions, but resulted in better gluability. Gluability of 25-year service life poles was the best and most comparable to untreated SYP. Five-year in-service poles and fi-eshly treated poles showed less favorable gluability. Superior gluability was obtained using RPF followed consecutively by PVA and casein. In reutilization of out-of-service poles into engineered wood products, pieces that have retained sufficient creosote to be effective against decay should be placed into ground contact. Similarly, pieces of poles with lower creosote content, and consequently better gluability, would be better utilized in non-ground contact areas of engineered wood products. Latewood percentage and angle of growth ring to the glueline also affected gluability. Latewood correlated positively with shear strength and negatively with wood failure. The lower the angle of the growth ring, the higher the shear and the greater the wood failure.