| |
|
|
|
|
|
Maximum Moment of a Non-Compact Or Slender
Webbed I
Beam Or Channel: |
|
|
|
Calculation: |
|
|
Designer/Checker: |
|
|
|
|
|
Input: |
|
|
|
|
|
|
|
|
|
(Note: All input Metric units are converted to English units
for the equations below and then the output English units are converted back to
Metric) |
|
|
|
From AISC F4 And F5: |
|
This calculation applies to: (a) doubly symmetric I-shaped members bent about
their major axis with noncompact webs; and (b) singly symmetric I-shaped members
with webs attached to the mid-width of the flanges, bent about their major axis,
with compact or noncompact webs; and (c) doubly symmetric and singly symmetric
I-shaped members with slender webs attached to the mid-width of the flanges,
bent about their major axis. |
|
|
|
|
|
|
|
|
|
Unbraced length (Lb - ft or m) |
|
|
Limiting laterally unbraced length for the limit state of yielding (Lp - ft or m) |
|
|
Steel yield strength (fy - ksi or MPa) |
|
|
Limiting laterally unbraced length for the limit state of inelastic
lateral-torsional buckling (Lr - ft or m) |
|
|
Depth of the beam (d - in or mm) |
|
|
Depth of the area in compression (y - in or mm) |
|
|
Thickness of the compression flange (tfc - in or mm) |
|
|
Width of the compression flange (bfc - in or mm) |
|
|
Effective radius of gyration (rt - in or mm)* |
|
|
Lateral-torsional buckling modification factor (Cb)** |
|
|
Moment of inertia, x-axis (Ix - in^3 or mm^3) |
|
|
Height of web (h - in or mm) |
|
|
Thickness of web (tw - in or mm) |
|
|
Width to thickness ratio of the flange (WTF = bf/2tf) |
|
|
Limiting slenderness of compact flange (WTFp) |
|
|
Limiting slenderness of noncompact flange (WTFr) |
|
|
*Effective radius of gyration, rts, can be conservatively approximated
for I shapes with a rectangular compression flange
as the radius of gyration of a section of the compression flange plus 1/3 of
the compression web area. |
|
|
**Cb can be conservatively taken as 1.00. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Output: |
|
|
Login to enable the Formulas!
|
|
|
|
|
Maximum moment of the beam, Mu = |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|