> For the complete documentation index, see [llms.txt](https://enercalc.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://enercalc.com/docs/sel-user-manual/calculation-modules/beams/steel-beam.md).
# Steel Beam
How to design single or multi-span steel beams for bending, shear, and deflection per AISC 360.
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{% column width="33.33333333333333%" valign="middle" %} Verification Example
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{% column width="66.66666666666667%" %} This example includes calculation details, references to design provisions, and step-by-step results for easy checking.
{% endcolumn %}
{% endcolumns %}
In this section, for each input tab we will review only the items that are unique to the STEEL material type.
For general information on the typical data input for all beams see the [Beams](/docs/sel-user-manual/calculation-modules/beams.md) topic.
This module offers complete design of single and multi-span steel members. Among its capabilities are:
* Single or multi-span (up to 8-span) beams.
* End fixity can be pinned, fixed, free or a combination.
* Steel member analysis and design are according to AISC 360.
* ASD or LRFD design methods can be selected.
* A complete steel section database is provided.
* Unbraced compression edge lengths can be specified in a variety of ways.
* Automatic member selection is provided.
## Inputs Window
### General
When steel is used, this tab includes input fields to set the values for yield stress and elastic modulus, as well as an option to set the Cb factor equal to 1, as shown in the screen capture below:
If Cb is not forced to 1, the program automatically calculates Cb based on the moment and direction of curvature at each Unbraced Length in the beam.
For convenience the module includes a built-in steel database. Click the  button to the right of the Fy entry and you will see the following table, which offers a number of commonly used steel grades:
### Beam Span Data
When steel is selected, the beam size selection is specifically for steel. You can select a section in 4 ways:
1 - Simply type the AISC name into the Steel Section Name field and press \[**Tab**].
2 - Click the  button and select from the built-in AISC section database.
3 - Click the \[**Auto Select**] button to have the module evaluate steel sections from the database according to your criteria.
4 - Select a steel section from the Quick-List tab as shown below:
### Span Loads
No differences from other materials.
### Loads All Spans
No differences from other materials.
### Load Combinations
No differences from other materials.
## Outputs Window
This set of tabs provides detailed results for the current calculation. The tabs in the upper right-hand corner of the screen allow you to select the major areas available for review: Calculations, 2D Sketch, Diagram and 3D Rendering.
### Calculations
The Calculations tab offers the following results options:
#### Summary Results
Provides details for shear, moment and deflection for the governing load combinations.
#### Max. Combinations
Provides detailed results for each beam segment for each load combination. This area was greatly enhanced in April 2026.
As background, it is well known and documented that points of inflection are not to be treated as brace points. The program no longer allows that option.
The following new behaviors have been introduced:
* An Unbraced Length is defined by the distance from one brace to another. At this time the Steel Beam module still assumes that both the top and bottom flange are braced at brace points, which include supports and user-defined brace locations. (The program now calculates one value of Cb for each unbraced length.)
* It is possible for one or more points of inflection to occur within an Unbraced Length.
* If one or more points of inflection occur within an Unbraced Length, it will be subdivided into two or more Design Segments over which only the top or the bottom is in compression.
This discretization was not present in previous versions. Previous versions always designed for the larger of the positive or negative moments. The program now performs separate flexural checks for positive moment and for negative moment, and reports intermediate values for all relevant failure modes for better optimization.
#### M-V-D Summary - Shears & Moments
Shows highly detailed moment and shear information for each beam and for each load combination. For multi-span beams using Automatic Unbalanced Live Load Placement there may be thousands of lines of results.
#### M-V-D Summary - Deflections
Shows highly detailed deflection results for all load combinations.
#### Support Reactions
Shows the reaction at each support for every load case and load combination.
* **Positive** (+) reactions act **upward**. For example, gravity loads typically produce positive (+) reactions.
* **Negative** (-) reactions act **downward**. For example, uplift loads typically produce negative (-) reactions.
### 2D Sketch
The 2D Sketch tab provides a graphic representation of the beam currently being designed:
### Diagram
The Diagram tab offers the ability to view shear, moment, and deflection diagrams for selected load combinations:
### 3D Rendering
The 3D Rendering offers a 3D view of the beam with many display controls:
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