Machinery's Handbook, 31st Edition
Wood 383 Shear Strength Parallel to Grain: Shear strength is a measure of the ability to resist internal slipping of one part upon another along the grain. The values listed in the table are averages of the radial and tangential shears. Tensile Strength Perpendicular to Grain: The tensile strength perpendicular to the grain is a measure of the resistance of wood to forces acting across the grain that tend to split the material. Averages of radial and tangential measurements are listed. Table 1. Mechanical Properties of Commercially Important US Grown Woods Use the first number in each column for GREEN wood; use the second number for DRY wood. Static Bending Maximum Crushing Strength (10 3 psi) Compression Strength Perpendicular to Grain (psi) Shear Strength Parallel to Grain (psi) Tensile Strength Perp. to Grain (psi) Modulus of Rupture (10 3 psi) Work to Max Load (in-lb/in 3 )
Basswood, American Cedar, N. white Cedar, W. red Douglas Fir, coast a Douglas Fir, interior W. Douglas Fir, interior N. Douglas Fir, interior S. Hemlock, Eastern Hemlock, Mountain Hemlock, Western Pine, E. white Fir, balsam
5.0 8.7 5.3 7.2 2.22 4.73 170 370 600 990 280 350 4.2 6.5 5.7 4.8 1.90 3.96 230 310 620 850 240 240 5.2 7.5 5.0 5.8 2.77 4.56 240 460 770 990 230 220 7.7 12.4 7.6 9.9 3.78 7.23 380 800 900 1,130 300 340 7.7 12.6 7.2 10.6 3.87 7.43 420 760 940 1,290 290 350 7.4 13.1 8.1 10.5 3.47 6.90 360 770 950 1,400 340 390 6.8 11.9 8.0 9.0 3.11 6.23 340 740 950 1,510 250 330 5.5 9.2 4.7 5.1 2.63 5.28 190 404 662 944 180 180 6.4 8.9 6.7 6.8 3.08 5.41 360 650 850 1,060 230 … 6.3 11.5 11.0 10.4 2.88 6.44 370 860 930 1,540 330 … 6.6 11.3 6.9 8.3 3.36 7.20 280 550 860 1,290 290 340 4.9 9.9 5.2 8.3 2.44 5.66 220 580 680 1,170 250 420 7.3 13.0 10.9 13.7 3.42 6.71 390 910 890 1,350 400 380 4.7 9.7 5.0 8.8 2.43 5.04 190 470 680 1,040 260 …
Pine, Virginia Pine, W. white
Redwood, old-growth 7.5 10.0 7.4 6.9 4.20 6.15 420 700 800 940 260 240 Redwood, young-growth 5.9 7.9 5.7 5.2 3.11 5.22 270 520 890 1,110 300 250 Spruce, Engelmann 4.7 9.3 5.1 6.4 2.18 4.48 200 410 640 1,200 240 350 Spruce, red 6.0 10.8 6.9 8.4 2.72 5.54 260 550 750 1,290 220 350 Spruce, white 5.0 9.4 6.0 7.7 2.35 5.18 210 430 640 970 220 360 a Coast: grows west of the summit of the Cascade Mountains in OR and WA. Interior west: grows in CA and all counties in OR and WA east of but adjacent to the Cascade summit. Interior north: grows in remainder of OR and WA and ID, MT, and WY. Interior south: grows in UT, CO, AZ, and NM. Results of tests on small, clear, straight-grained specimens. Data for dry specimens are from tests Weight of Wood.— The weight of seasoned wood per cord is approximately as follows, assuming about 70 cubic feet of solid wood per cord: beech, 3300 pounds; chestnut, 2600 pounds; elm, 2900 pounds; maple, 3100 pounds; poplar, 2200 pounds; white pine, 2200 pounds; red oak, 3300 pounds; white oak, 3500 pounds. For additional weights of green and dry woods, see Table 2. Weight per Foot of Wood, Board Measure.— The following is the weight in pounds of various kinds of woods, commercially known as dry timber, per foot board measure: white oak, 4.16; white pine, 1.98; Douglas fir, 2.65; short-leaf yellow pine, 2.65; red pine, 2.60; hemlock, 2.08; spruce, 2.08; cypress, 2.39; cedar, 1.93; chestnut, 3.43; Georgia yellow pine, 3.17; California spruce, 2.08. For other woods, divide the weight/ft 3 from Table 2 by 12 to obtain the approximate weight per board foot. of seasoned material adjusted to a moisture content of 12%. Source: US Department of Agriculture: Wood Handbook . Effect of Pressure Treatment on Mechanical Properties of Wood.— The strength of wood preserved with creosote, coal-tar, creosote-coal-tar mixtures, creosote- petroleum mixtures, or pentachlorophenol dissolved in petroleum oil is not reduced. However, waterborne salt preservatives contain chemicals, such as copper, arsenic, chromium, and ammonia, which have the potential of affecting mechanical properties
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