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D12.A.6.7 Rectangular massive box (prismatic)

The prismatic section is assumed to be a rectangular massive box and the von Mises stress is checked at 3 locations as shown in figure below.

Note: Code check of the general purpose prismatic cross section is not available.
Note: Note that "b" may not be much greater than "h". If that is the case, define the member with h > b and beta angle 90° instead.

Section Properties

where
Ax , Ay , Az , Ix , Iy , and Iz , b, h
=
are user-specified. Refer to TR.20.2 Prismatic Property Specification.
b
=
ZD
h
=
YD
Cw
=
1 24 b 2 ( h b ) 2 h + b h 2 b 2 , ref.NS app C3.

General Stress Calculation

σ = σ x + σ b y + σ b z = F x A x + M y I y z + M z I z y
τ = τ x + τ y + τ z = τ x , max ( c b ) 2 + V y A y + V z A z
τ x , max = M x ( 1.5 h + 0.9 b ) 0.5 h 2 b 2

ref. [4] tab. 20, case 4 at midpoint the largest (i.e, point 2)

Stress calculation at selected stress points

Point No σx σby σbz τx τy τz
1 F x A x M y I y b 2 M z I z h 2 τ x , max b 2 b 2 + h 2 0 0
2 M y I y b 2 0 τ x , max F y A y 0
3 0 M z I z h 2 τ x , max b 2 h 2 0 F z A z