Structural Shapes Standardization

aisc is the standard. buy a manuel.

There is no single parameter because the members have different uses in a structure. They were arrived at from experience.

Different shapes have different basis. For example, S-shapes (AKA I-beams) are made with a single set of rollers producing many weight beams by moving them apart. The flanges are pretty much the same, but the web is different thicknesses. WF (wide flange) shapes use one set of rollers to form the web and a second set to form the flanges, so both the flange and the web thickness can change for a single depth beam. Angles also use a common set of rolls for each nominal size, with the leg thickness being determined by moving the rolls to different standard distances.

• The American Institute for Steel Construction AISC is the organization interested in standardization of structural shapes.

• The attached handbook of Structural Steel Properties & Dimensions is printed at French, English & German: http://www.4shared.com/office/fUy0QA0I/file.html

Many standards govern structural members, from steel production methods, to rolling methods, to testing methods, to dimensional constraints, to construction methods using structural members. These standards also vary globally.

In America - in addition to the already mentioned AISC, we also have:

ASTM A36 / A36M - 08 Standard Specification for Carbon Structural Steel

ASTM A6 / A6M - 11 Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, and Sheet Piling

ASTM A700 - 05 Standard Practices for Packaging, Marking, and Loading Methods for Steel Products for Shipment

ASTM A751 - 11 Standard Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products

etc...

Now, are there mills out there that produce steel products not in accordance with the appropriate standards... sure. But if you're looking to buy structural members to build buildings and bridges, I'd stay away from Acme Beams and Chicken Feed Store.

In America, a good reference of reputable manufacturers that adhere to the appropriate standards of manufacturing and testing, along with a list of their common shapes can be found here:

http://www.aisc.org/bookstore/itemRedirector.aspx?id=15292

Otherwise, you can go here to get your other questions answered and/or inquire about reputable/certified manufacturers in your global location:

http://www.aisc.org/askaisc/default.aspx?id=2240