Singly Symmetric Combination Section Crane Girder Design Aids

Crane runway girders are distinguished by long, unbraced lengths and biaxial bending. Combination sections consisting of a W-shape with a channel cap are typically efficient for these conditions, but time consuming to design due to the iterative process required due to biaxial bending and the complex stability equations provided in the 2005 AISC Specification. This paper presents developed Zx (plastic section modulus) tables and flexural strength graphs and introduces a trial section selection method. Included herein are updated design charts to allow for fast and efficient analysis of the typical combination sections provided in Table 1-19 of the 13th edition AISC Steel Construction Manual. Also presented is an overview of crane girder design procedures and an abbreviated design example.