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### Channel Section Intermediate Torque Applied No1 Roarks Formulas for Stress and Strain Equations and Calculator

Channel Section with Concentrated Intermediate Torque applied Deflection and Stress Equations and Calculator #1a.
Formulas for the elastic deformations of uniform thin-walled open members under torsional loading.

Per. Roarks Formulas for Stress and Strain - Formulas for torsional properties and stresses in thin-walled open cross sections, Table 10.2.

Section Dimensional Definitions
Figure 1

Left end free to twist and warp, right end free to warp but not twist.
Concentrated intermediate torque of Channel Beam

Figure 2

Concentrated intermediate torque of Channel Beam Orientation Declarations Image
Figure 3

Channel Section Properties Constants Formulas See: Figure 1

Selected maximum values of stress and torsion

throughout the thickness at corners A and D

 throughout the thickness at a distance from corners A and D

Left end free to twist and warp, right end free to warp but not twist Formulas:

The following constants and functions are hereby defined in order to permit condensing the tabulated formulas which follow.
Concentrated intermediate torque See Figure 3

Where (when used in equations and this calculator):

Point 0 indicates the shear center se "Concentrated intermediate torque of Channel Beam Orientation Declarations image ";
e = distance from a reference to the shear center (in, m);
K = torsional stiffness constant (in4, m4);
C =warping constant (in6, m6);
τ1 = shear stress due to torsional rigidity of the cross section (lbsf/in2, m2);
τ2 = shear stress due to warping rigidity of the cross section (lbsf/in2, m2);
σx = bending stress due to warping rigidity of the cross section (lbsf/in2, m2);
E = modulus of elasticity (lbs/in2, m2);
G = modulus of rigidity (shear modulus) of the material (lbs/in2, m2)
To = applied torsional load (in-lbs, N-m);
to = applied distributed torsional load (lbsf/in, N/m);
TA and TB are the reaction end torques at the left and right ends, respectively (in-lbs, N-m);
θ = angle of rotation at a distance x from the left end (radians).
θ', θ'', θ''', = are the successive derivatives of y with respect to the distance x.
Cw = the warping constant for the cross section;

All rotations, applied torsional loads, and reaction end torques are positive as shown (CCW when viewed from the right end of the member)

Unit step function defined by use of ⟨ ⟩
⟨ x - θ ⟩0

if x < a, ⟨ x - a ⟩n =0;
if x > a, ( x - a) n ;

The function sinh β⟨ x - a ⟩ is defined as zero if x < a

β = ( KG/CwE)1/2

Supplemental selected special cases and maximum values (not included in calculator), See Figure 2.
Large image click this text

Reference:
Roarks Formulas for Stress and Strain, 7th Edition, Table 10.2 and 10.3 Formulas for torsional properties and stresses in thin-walled open cross sections.