# Thread: Moment of Inertia Hat Section

1. ## Moment of Inertia Hat Section

How does one compute the moment of inertia of a hat section?
Do we have a standard formula for this?

2. Hi, and welcome. First off, is it a standard form made by a manufacturer? If so they should be able to give you the needed load information.

It gets tricky in breaking the section into simple shapes and adding them together. Not quite as simple to do as that explanation.

Give us a better idea if what you are trying to do and we can give a better idea on how to go about it. A picture paints a thousand words.

3. Hello,
I do not have any contact with any manufacturer. I am a Graduate student and need this information for a project. I did break it up in to smaller rectangles and did the calculation, but want to cross check it if there is a formula.
I just require the MI of an all right angled hat section about its symmetric axis.
I hope I were clear on this. Let me know in case you need more information.

4. I'm sure one could derive a plug and calculate formula, however you could go ahead and use composite section method.

Also, if you have CAD you could model the geometry and the software calculate for you.

5. "I did break it up in to smaller rectangles and did the calculation, but want to cross check it if there is a formula."

I'm puzzled. Do you have the reference axis for the calculation. And how many "smaller" rectangles do you have.
If you know how to get the MI of a rectangle, isn't that all you need , since any hat section is the sum of rectangles, or are there other geometries.

Why don't you show us a sketch oof the hat and maybe someone here can show you how it is done, since I'm getting the feeling that you are not sure.

6. +1 Zeke.

Especially this comment... "since I'm getting the feeling that you are not sure" as the guy says "and did the calculation" and just wants to validate. If that's the case then Ram275, how about scanning your calculations and we can look at them and tell you if the process is correct.

Zeke, I think you may be on to something here.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•