2L8×4×1/2LLBB double angle

Detailing dimensions and section properties from the AISC Shapes Database, 16th Edition. Values are shown to the nearest 1/16 in. as they appear on a shop drawing.

2L8×4×1/2LLBB has a 8 in. long leg and a 4 in. short leg, 1/2 in. thick, in contact back to back.

It is a double angle set with its long legs back-to-back.

At 39.2 lb per foot it is one of the 42 2L8×4 sizes, which run from 34.4 to 74.8 lb/ft.

For strong-axis bending its section modulus is Sx = 15 in³ and its moment of inertia Ix = 77.2 in⁴, with a plastic modulus Zx = 26.2 in³.

Detailing dimensions

Long leg8"
Short leg4"
Thickness (t)1/2"

Section properties

Weight39.2 lb/ft
Area (A)11.6 in²
Ix77.2 in⁴
Sx15 in³
Zx26.2 in³
rx2.58 in
Iy22.1 in⁴
Sy5.52 in³
Zy9.91 in³
ry1.38 in

Other 2L8×4 sizes

Same nominal size, different weight — useful when you are checking a substitution or a lighter section.

2L8×4×7/16LLBB2L8×4×7/16×3/8LLBB2L8×4×7/16×3/4LLBB2L8×4×7/16SLBB2L8×4×7/16×3/8SLBB2L8×4×7/16×3/4SLBB2L8×4×1/2×3/8LLBB2L8×4×1/2×3/4LLBB2L8×4×1/2SLBB2L8×4×1/2×3/8SLBB2L8×4×1/2×3/4SLBB2L8×4×9/16LLBB2L8×4×9/16×3/8LLBB2L8×4×9/16×3/4LLBB2L8×4×9/16SLBB2L8×4×9/16×3/8SLBB2L8×4×9/16×3/4SLBB2L8×4×5/8LLBB2L8×4×5/8×3/8LLBB2L8×4×5/8×3/4LLBB2L8×4×5/8SLBB2L8×4×5/8×3/8SLBB2L8×4×5/8×3/4SLBB2L8×4×3/4LLBB

All 2L8×4 sizes and dimensions →

Similar weight double angles

Comparable 39.2 lb/ft sections in other double angle sizes.

2L6×6×1/239.2 lb/ft · Sx 9.18 in³2L6×6×1/2×3/839.2 lb/ft · Sx 9.18 in³2L6×6×1/2×3/439.2 lb/ft · Sx 9.18 in³2L5×3-1/2×3/4LLBB39.6 lb/ft · Sx 8.52 in³2L5×3-1/2×3/4×3/8LLBB39.6 lb/ft · Sx 8.52 in³2L5×3-1/2×3/4×3/4LLBB39.6 lb/ft · Sx 8.52 in³2L5×3-1/2×3/4SLBB39.6 lb/ft · Sx 4.4 in³2L5×3-1/2×3/4×3/8SLBB39.6 lb/ft · Sx 4.4 in³

Detailing values are rounded to the nearest 1/16 in. per the AISC Steel Construction Manual. Verify critical dimensions against the current Manual before fabrication. Need 2L8×4×1/2LLBB cut, formed, or fabricated? Huntington Steel & Supply Co.

Browse more: Double angles · Steel Beam Size Chart

Interactive drawing