3038 



Chapter 24 



Table 24-28. — Modulus of rupture and modulus of elasticity of phenolic-bonded panels 

 with southern pine veneer faces and cores of southern hardwood veneer flakes (Hse 1 976) 



Thickness of 



face veneers (inch) 



and type of flake core' 



M0R2 



MOE- 



Parallel-^ Perpendicular"^ Parallel Perpendicular'^ 



- Psi — Million psi 



ONE FACE VENEER EACH SIDE 



1/10 



Random 9,814 2,050 1 .942 0.209 



Oriented 7,125 2,680 1.685 .414 



Three-layer 6,588 2,833 1.876 .409 



1/16 



Random 10,400 2,453 1 .696 .298 



Oriented 5,919 6,511 1.445 .791 



Three-layer 8,010 6,126 1.359 .862 



1/24 



Random 7,245 3,456 1 .434 .437 



Oriented 4,495 6,640 1 .049 1 .003 



Three-layer 6,902 6,407 1.212 1 .073 



TWO FACE VENEERS CROSS-LAMINATED EACH SIDE 

 1/10 



Random 5,853 — 1 .914 — 



Oriented 11,359 — 1.952 — 



Three-layer 6,017 — 1 .920 — 



1/16 



Random 11 ,562 — 1 .820 — 



Oriented 15,843 — 1.983 — 



Three-layer 8,617 — 1.846 — 



1/24 



Random 6,753 — 1 .344 — 



Oriented 12,281 — 1.748 — 



Three-layer 6,988 — 1.564 — 



'Flakes were of rotary-cut veneer 3 inches long, 0.015 inch thick, and 3/8-inch wide. See figure 

 24-50 for panel construction. Core flakes were a mixture of species: 50 percent southern red oak, 25 

 percent hickory, and 25 percent sweetgum. 



^In stress parallel or perpendicular to grain of outermost face veneers. 



•'Of the specimens with 1/10-inch veneers, 86 percent failed in horizontal shear; 27 percent of 

 those with 1/16-inch face veneers failed in horizontal shear. These shear failures precluded accurate 

 determination of true MOR with these veneer thicknesses. 



'^Two-ply panels were not tested perpendicular to the grain of the face plys. 



