Equivalent Beams

Your understanding is correct:

1) Find the shape with the moment of inertia with equal or higher value in US norms

2) Check the material quality

3) Check if the geomery of the chosen US shape fits into the design made with EU norms

Additional info:

I am living and working in the United States. I typically deal with W and S shapes for steel I-beams and don't have much experience with foreign beam shapes.

When I said that the dimensions don't match any standard U.S. shape I meant that I found the dimensions of the HEB100 in metric units and converted them to English units. I doubted that is the correct way to find an equivalent beam and didn't find any W or S shape that matched the dimensions.

I calculated the moment of inertia of the HEB100 then found a W shaped that had a close but slightly larger MOI than the HEB. Is this method valid?

Welcome aboard! As a non-mechanical engineering person, I can but speculate, but doing so, it sounds as if it should be valid. A better (even slightly) MOI would be appropriate. The other concern, obviously, is physical dimension - does it fit?

At the risk of stating the obvious but with the intention of giving a complete picture, you need to get the properties of the european beams and compare the following:

• height
• depth
• flange
• web

If you are within 0.5mm (especially erring on the side of caution) then the calculations supporting the design will probably still be valid (under european regulations). The steel needs to be of the same equivalent grade US. You can then proced to verify the design using your US codes.

Form my british/french experience, beams can generally be found of similar but not exact dimensions. Beam and column sizes are the general rule. Beam width is about half the depth whereas column flanges are about the same width as their depth.

I should have said in my original posting. The beam doesn't have to be exact dimensionally. Its being used as a stiffener so it only has to be able to carry the same load.

The best way is to have equivalent load carying capability.

You have to look at the kind of loading and choose either the same type of beam or an other which will offere same safety.

Thank you to everyone who responded for taking time and effort from your schedule to help me out.

I'm a new mechanical engineer working in the waste-to-energy industry. I graduated from Rose-Hulman in Terre Haute, Indiana back in May of 2007. This is my first real-world position. Thank you all again for your help.