CMAA Specification 74 - Local Buckling and Compression

Morning all.

I am an EIT working for an ag equipment manufacturing company in Saskatchewan, Canada. I am currently doing some analysis on a few of the older overhead cranes in our facility that weren't properly engineered originally. As the size, and consequently the weight, of our equipment increases, so is out concern for the safety of our hoists.

To make future analysis of our runways and bridges simpler, I have been putting together a spreadsheet that completes the calculations for the crane structure using all wide flange beams (which is what we have always used for our overheads). However, I have reached two sections that I am not real clear on.

First, section 3.4.5 "Buckling Analysis". This section refers to section 3.4.8 which seems to be strictly for Box Girder sections. Does 3.4.5 apply to single web runways?

Second, section 3.4.6 "Compression Members", both axial and bending loads are taken into account. In what case, or on what elements of the structure, would this be a consideration? Only if they are in compression, or is the "compression" in the title of the section refering to the top flange of the section? I am trying to determine how this is relevant, and if it is, how to determine the axial loads, as I believe they would only be a result of deflection of the runways.

Thank you for any and all help/advice.