Steel Beams Design

The program performs the design of a steel member when subjected to shear and bending about its strong axis, based on the Allowable Stress Design Method of the American Institute of Steel Construction (AISC) 9th Ed.

The program computes the maximum bending moment, shear force, and vertical deflection induced by the applied loads, and compares the stresses in the beam against the allowable stresses according to the beam geometry.

In addition, the program works on a database of the steel sections and, therefore, it is possible to specify any section to be analyzed without the necessity of entering its properties.

Input Data

The required input data consists of steel yield strength, member length, and unbraced length. In addition, it is possible to consider a uniformly distributed load per unit length, and up to four concentrated loads along the beam and two bending moments at the ends.

This allows the designer to model beams with any degree of fixity at the ends, such as individual spans of continuous beams, or beams with fixed supports. Figure to the right shows the required input data and the sign convention.

Example

Given the laterally unsupported girder shown in the figure to the left for a crane runway in an industrial warehouse, select the lightest W-section that also limits the maximum deflection to L/360. Use A36 steel.

Output

To specify the section to be analyzed, choose the Select option from the Design menu or double click the section designation field in the template.

Left click on the LIGHTEST button to have the program search the lightest section that satisfies the design criteria. Left click on the FIXITY button to specify the fixity condition at both ends.

The program automatically computes the maximum shear and bending stresses, as well as the maximum beam deflection, and checks the adequacy of the design.

Figure to the right shows the template of this program, as well as the graph generated by the program with the example data and results.