Timbers – 5" and larger

6x8

Standard: DOC PS 20 / NDS SupplementSource: Nominal − ½" (green), calculated
xyb = 5.5d = 7.5
Cross-section, to scaledimensions in inches

Dimensions

Depthd
7.5in
Widthb
5.5in

Mass and area

Cross-sectional areaA
41.25in²
Outside perimeterP
26in

Strong axis x–x

Moment of inertiaIx
193.4in⁴
Elastic section modulusSx
51.56in³
Plastic section modulusZx
77.34in³
Radius of gyrationrx
2.165in

Weak axis y–y

Moment of inertiaIy
104in⁴
Elastic section modulusSy
37.81in³
Plastic section modulusZy
56.72in³
Radius of gyrationry
1.588in

Torsion and stability

Torsional constantJ
228.4in⁴

Equivalents in other standards