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Sample calculation · Timber

Beam in biaxial bending

Design codeSIA 265:2021

b = 680 h = 280
Strength class
GL24h
Section
680 × 280 mm
Moment, y-y
My,d = 93 kN·m
Moment, z-z
Mz,d = 1 kN·m

PassBiaxial bending

η = 0.76≤ 1.0076 % of the capacity used

σm,y/fm,y + σm,z/fm,z ≤ 1§ 4.2.3.1 (14)

StepValueUnitRef.
Bending stress, y-yσm,y,d = My,d / Wy 10.4667N/mm²
Bending resistance, y-yfRd,m,y = km,y · fm,d · kh,y · ksys · ηt · ηw 13.814N/mm²§ 4.2.9.1 (38)
Bending stress, z-zσm,z,d = Mz,d / Wz 0.0463N/mm²
Bending resistance, z-zfRd,m,z = km,z · fm,d · max(kh,z ; ksys) · ηt · ηw 12.800N/mm²§ 3.4.2.2
Biaxial bending η = 0.761Pass§ 4.2.3.1 (14)

+ 9 more steps in the module: section moduli, height factors, lateral torsional buckling.

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