WOOD - Materials for Civil and Construction Engineers - page 430

Load

Load

(a) (b)

FIGURE 10.18 Axis convention used for defining loading conditions for
Laminated Veneer Lumber.

T ABLE 10.8 Design Properties for APA-EWS Performance Rated LVL (APA-EWS, 2000)

Allowable

Allowable tensile Compressive

extreme stress stress Edgewise Stress

APA-EWS Bending fiber parallel parallel shear perpendicular

Stress Class modulus stress to grain to grain stress to grain

10 6 psi

( ) (psi) (psi) (psi) (psi) (psi)

1.5E-2250F 1.5 2250 1500 1950 220 575

1.8E-2600F 1.8 2600 1700 5400 285 700

1.9E-2600F 1.9 2600 1700 2550 285 700

2.0F-2900F 2.0 2900 1900 2750 285 750

2.1E-3100F 2.1 3100 2200 3000 285 850

Parallel and Oriented Strand Lumber As with OSB, strands of wood can be
glued together into structural members. Depending on the length of strand
and degree of orientation, products are classified as parallel strand lumber,
laminated strand lumber, or oriented strand lumber.
Parallel strand lumber is a composite of wood strand elements, with wood
fibers oriented primarily along the length of the member. The smallest dimen-
sion of the strand must be less than 6.4 mm (0.25 in.) and the average length
of the strand must be 150 times the smallest dimension. Typically, the strands
are 3 mm (0.125 in.) thick, 19 mm (0.75 in.) wide and 0.6 m (24 in.) long.
A waterproof structural adhesive, such as phenol-resorcinol-formaldehyde,