Steel Column (ASD, AISC 360-16)

Design hot-rolled steel columns and posts to AISC 360-16 ASD using service-level loads. Checks cover allowable axial compressive strength, flexural and flexural-torsional buckling, and combined axial-plus-bending interaction. Column axial load links from beam reactions above and passes down to footing calculations below.

This calculator uses an earlier code edition (AISC 360-16 (ASD)). It stays available for existing projects. For new designs, check the [Calculator Library](/docs/calculators/us) for the current edition. ## Method & scope | Property | Detail | | ---------------- | ----------------------------------------------------------------------------------------------------------------------------- | | Design standards | AISC 360-16 (ASD) | | Regions | United States | | Presets | Generic Concentrically-Loaded Column, Interior Isolated Column, Exposed Outdoor Isolated Column | | What it checks | Structural analysis, Axial compression capacity, Flexural capacity, Combined axial compression and bending, Axial deformation | #### Calculation method The Steel Column (ASD, AISC 360-16) calculator designs hot-rolled steel columns and posts using Allowable Stress Design. It runs a first-order structural analysis to determine service-level demands, then applies AISC 360-16 allowable capacity equations for all limit states. ##### Structural analysis The calculator performs FEA on the column as a beam-column, resolving axial forces, moments, and deflections under service loads. End conditions (pinned, fixed, roller) are specified at each support. Concentrated axial loads and distributed lateral loads can be applied at any height along the column. A first-order moment amplification factor accounts for P-delta effects; the member is assumed to be part of a braced frame. ##### Axial compression capacity Allowable axial compressive strength follows AISC 360-16 Chapter E: **utilization = Pa / (Pn / Omega\_c) ≤ 1.0** where Omega\_c = 1.67. The nominal strength Pn is governed by flexural buckling about the weak axis for standard doubly-symmetric shapes. For singly-symmetric and unsymmetric sections, flexural-torsional buckling is also evaluated. Slender element reduction factors (Q) are applied per Section E7 where local buckling limits the section capacity. ##### Flexural capacity When moments are present from eccentricity or lateral loads, allowable flexural strength is checked per AISC 360-16 Chapter F: **utilization = |Ma| / (Mn / Omega\_b) ≤ 1.0** where Omega\_b = 1.67. Compact, non-compact, and slender section classifications per Table B4.1b govern the applicable strength equations. Lateral-torsional buckling is evaluated based on the unbraced length relative to Lp and Lr. ##### Combined axial compression and bending The AISC H1-1 interaction check (ASD form) covers simultaneous axial and biaxial bending demands: * For Pa / (Pn / Omega\_c) ≥ 0.2: (Pa \* Omega\_c / Pn) + (8/9) \* (Mxa \* Omega\_b / Mnx + Mya \* Omega\_b / Mny) ≤ 1.0 * For Pa / (Pn / Omega\_c) \< 0.2: (Pa \* Omega\_c / 2Pn) + (Mxa \* Omega\_b / Mnx + Mya \* Omega\_b / Mny) ≤ 1.0 Both strong- and weak-axis moments are included, covering the full biaxial bending case. ##### Axial deformation Axial shortening under service loads is calculated and reported for serviceability review where column shortening matters to the structural system. ##### Outputs Results are displayed as color-coded utilization ratios for each limit state alongside code clause references. The governing check and critical load case are summarized for easy QA and report documentation. ## How to use it Open it from **Run calc** in the About this calculator panel above. To start from a typical setup, choose one of the presets listed there. Work through the input sections from top to bottom. Click any input label to see its reference explanation, clause, conditions and assumptions. See [Checks, References, Conditions and Assumptions](/docs/running-calculations/checking-results/checks-references-conditions-assumptions). Check the utilization of each governing check in the summary, then export a PDF report. See [Views and Export](/docs/running-calculations/exporting-reports/views-and-export). ## Common questions The calculator uses Allowable Stress Design (ASD) per AISC 360-16. Unfactored (service-level) load demands are compared against allowable capacities, which are the nominal strengths divided by the safety factor Omega. Key inputs include column height, end conditions (pinned, fixed, roller), service-level axial loads with optional eccentricity, distributed lateral loads, and effective length factors Kx and Ky. The steel section is selected from the AISC database or entered as a custom shape. The calculator checks allowable axial compressive strength (flexural buckling and flexural-torsional buckling), strong- and weak-axis allowable flexural strength including lateral-torsional buckling, and combined axial compression plus biaxial bending interaction per AISC 360-16 Chapter H (ASD form). The ASD version works with service-level (unfactored) loads and allowable capacities (Pn / Omega\_c, Mn / Omega\_b). The LRFD version works with factored loads and phi-reduced capacities. Both reference AISC 360-16 and will produce equivalent designs when the same load combinations are applied correctly. ASD is often preferred for projects with established service-load workflows. Kx and Ky are entered directly. A value of 1.0 (pin-pin) is conservative for braced frames. For partially restrained connections the alignment chart method in AISC Commentary provides appropriate K-factor guidance. Yes, column axial load can be linked from beam reaction outputs above, and the resulting column base reaction links to a footing or base plate calculation below. Changes propagate automatically across the full load path. ## Next steps Complete list of Calcs.com design calculators available for United States projects (AISC, ACI, NDS, ASCE 7, IBC, and related standards). Design hot-rolled steel columns and posts to AISC 360-22 (ASD). Checks axial compression, flexural buckling and combined axial and bending. Design hot-rolled steel columns and posts to AISC 360-16 (LRFD). An earlier code edition, kept for existing projects. Design and analyze steel columns and posts to AISC 360-22 (LRFD). Multiple end fixities with traffic-light checks for moment, axial, and deformation. Design steel beams to AISC 360-16 (ASD) with multiple supports and loads. An earlier code edition, kept for existing projects.