> 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-with-torsional-load.md). # Steel Beam with Torsional Loads How to analyze and design a single-span steel beam for shear, bending, and torsion per AISC Design Guide 9. The Steel Beam with Torsional Loads module offers the ability to analyze and design a single-span steel beam for applied loads that create shear, bending, and torsion per the methodology of AISC Design Guide 9. It can be a useful tool for situations where beams have concentrated or distributed loads that are applied eccentrically, or where beams are subjected to torsional moments. **General:** The General tab allows you to set the span length, and support conditions in much the same way that this information is provided in the other beam modules. Refer to the [Beams](/docs/sel-user-manual/calculation-modules/beams.md) topic for additional explanation, but remember that this particular module is limited to single-span conditions. In addition to these pieces of data, the General Data tab also provides input fields for the compression edge lateral bracing condition, the design method, material properties, and an option to force the Cb value to 1.0. ## Torsional End Restraints The support buttons labeled "Warp" at each end of the beam diagram allow you to control the restraint of cross-sectional warping at each end of the beam. This impacts the way in which torsional stresses are handled in the analysis. The following options are available when defining torsional end restraints: * **Left Pinned, Right Pinned:** Cross-sectional warping is **unrestrained** at both ends. * **Left Fixed, Right Fixed:** Cross-sectional warping is **restrained** at both ends. {% hint style="info" %} **NOTE:** Regardless of the chosen restraint options, both supports are always assumed to be fixed from a statics and stability standpoint, meaning they will exhibit some torsional reaction. The restraint settings only control whether cross-sectional warping is restrained or not. {% endhint %} Shapes of open cross-sections (like W and C) tend to warp under torsional loading. If this warping is unrestrained, only pure torsional stresses are present per AISC Design Guide 9 §4.1.2 and §4.1.3. However, when warping is restrained, additional direct shear stresses as well as normal flange stresses due to warping are considered. For closed cross-sections (like pipe and HSS), the effect of warping is negligible whether restrained or not per AISC Design Guide 9 §4.6.2. Therefore, these stresses are neglected from the analysis. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-497688806545c7d44c7460f3f8cf1bd6dcbfcac0%2Fclip0376_was_BMP.jpg?alt=media) **Beam Span Data:** The Beam Span Data tab is used to specify the span length, the allowable deflection ratios, and to select the steel section under consideration. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-641e6dae42d73e4babde0aacc061f384c9da985d%2Fclip0377_was_BMP.jpg?alt=media) **Span Loads:** The Span Loads tab allows you to specify loads on one span at a time. The behavior of the tools on this tab is very similar to the tools described for use in the other beam modules, except that it introduces the ability to specify load eccentricities and the ability to indicate that concentrated moments should be considered as torsional moments. Refer to the [Beams](/docs/sel-user-manual/calculation-modules/beams.md) topic for additional explanation. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-87045298662113a09e054fa9bce0982b1de0c5e7%2Fclip0378_was_BMP.jpg?alt=media) **Load Combinations tab:** The Load Combinations tab provides a view of the load combinations that will be analyzed. It also offers the ability to: * Select a different set of load combinations, * Modify the values used as load factors, and * Turn certain combinations on and off. Refer to the [Beams](/docs/sel-user-manual/calculation-modules/beams.md) topic for additional explanation. The Steel Beam with Torsional Loads module offers output options that are analogous to the output options provided by the other beam modules, with the exception that the results include torsional design considerations. The right half of the screen is dedicated to the display of results. The strip of tabs in the top right-hand corner of the display allows you to choose between Calculations, 2D Sketch, Diagram and 3D Rendering as explained below: **Calculations:** The Calculations tab offers four sub-tabs: Summary Results: Displays extreme flange normal stress, extreme flange and web shear stress, extreme deflections, extreme rotations, and extreme reactions. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-1354c1c82435ca3a6727b43851248496812b39f5%2Fclip0379_was_BMP.jpg?alt=media) Maximum Combinations: Displays maximum stress ratio, extreme moments and shears, flange normal stresses due to bending and due to torsion, flange shear stress due to torsion, web shear stress due to bending and due to torsion, for all load combinations. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-72097b00625eaaf45a37b4d010af896c655ad8fb%2Fclip0380_was_BMP.jpg?alt=media) M-V-D: Summary > Shears & Moments: Displays moment, shear, unbraced length, flange normal stress, flange shear stress, and web shear stress at small increments along all spans. Moment, shear, and stresses are displayed for all load combinations. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-2a3c0aa15c2534ebcc62d6d2491ab2c426cfa3e2%2Fclip0381_was_BMP.jpg?alt=media) M-V-D: Summary > Deflections & Rotations: Displays deflections and rotations at small increments along all spans. Deflection is displayed for service load combinations only. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-650f0bcdfa715f7bfa5d66d3c79a2661b153159e%2FSBwTL%20Deflections_was_BMP.jpg?alt=media) **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. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-9ff1eca78316954d1bec34d8668113c4a9a8d024%2Fclip0382_was_BMP.jpg?alt=media) **2D Sketch:** Displays a sketch of the beam, indicating span lengths, support conditions, and applied loads. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-f9723ca615f5df396c2959ab6263e8e5c6b0eb05%2Fclip0383_was_BMP.jpg?alt=media) **Diagram:** Displays a graphic depiction of the beam with superimposed graphs of Moment, Shear, Deflection or Rotation for a selected load combination, or for an envelope of all load combinations. ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-958488cdabdc64fe2d221e907e9b01577b1543c3%2Fclip0384_was_BMP.jpg?alt=media) **3D Rendering:** Displays a 3D graphic depiction of the beam many display options: ![](https://3283832020-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiBJmBoewuy4ZcBC7RF3m%2Fuploads%2Fgit-blob-556f09dba38c8358b6f54c39d728990b20c925f2%2FSBwTL%203D%20rendering_was_BMP.jpg?alt=media) --- # Agent Instructions This documentation is published with GitBook. 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