Gluability of out-of-service utility poles

This investigation determined the gluability of weathered, out-of-service s outhern yellow pine (SYP) (Pinus spp.) utility poles. Three types of adhesi ves 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, esp ecially in the outer and upper portions, 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 freshly treated poles show ed less favorable gluability. Superior gluability was obtained using RPF fo llowed consecutively by PVA and casein. In reutilization of out-of-service poles into engineered wood products, pieces that have retained sufficient c reosote to be effective against decay should be placed into ground contact. Similarly, pieces of poles with lower creosote content, and consequently b etter gluability, would be better utilized in non-ground contact areas of e ngineered wood products. Latewood percentage and angle of growth ring to th e glueline also affected gluability. Latewood correlated positively with sh ear strength and negatively with wood failure. The lower the angle of the g rowth ring, the higher the shear and the greater the wood failure.