• Coldwell, Donald L.
  University of Maine Graduate School
  

An investigation was constructed to determine selected strength characteristics of eastern spruce plywood, using standard ASTM tests.

Plywood panels were prepared, both at a commercial source and in the laboratory, by similar processes. The characteristics that were evaluated were fiber stress at proportional limit and modulus of rupture in bending; maximum tensile strength in tension; maximum crushing strength in compression; toughness; nail withdrawal resistance; and glueline shear strength.

There appear to be no statistically significant difference between the characteristics of the commercial and laboratory plywood, and on the basis of this study, eastern spruce appears to be a suitable species for structural grades of softwood plywood. It also appears that eastern spruce plywood might be upgraded from a group 3 to a group 2 American Plywood Association classification, on the basis of the test results determined by this investigation.