Bending Stresses On A Plate

[LIGWY]

Calculating bending stresses to assure a plate can handle the loading? How is this calculated? Do you use the beam diagrams in ASD? and use it as a one-way?

 

[J1D]

Plate bending stress calculation is rarely the same as a beam. Check books like Formulas of Stress & Strain, etc. Or give more info for the plate and loading.

 

[Tomfh]

As J1D mentioned, Roarks Formulas of Stress and Strain is good for this type of problem.

What sort of plate is it?

 

[JStephen]

Using the beam diagrams in AISC and treating it as a beam in one direction is a conservative approximation. If that gives unreasonable results, then look into the plate formulas or other methods.

 

[LIGWY]

I have a 3/8" plate that is span over a 26'x6' area and is supported every 4'3". The circumference is welded. I have a uniform load for the area at 2,200 lbs/ft or a 515 lbs/ft^2 and I also have a point load that is 4,985 lbs (there are two of them at 3' apart)

When I do a simple beam I feel I am not geeting reasonable results. And I can not find any resources at our office on plate theory. (no one can find it)

 

[Kwan]

As mentioned before, Roarks Formulas of Stress and Strain is an awesome reference for this analysis. I'd suggest getting the office to buy one. In the meantime, check out this site

http://www.xcalcs.com.

The site has some plate bending calculators. I've never verified the results of this site (i just use Roark). Anyway, I would suggest running full fixed edges and pinned edges to cover the two extremes.

 

[J1D]

The bending stress of the plate, if you simply take it a s a beam, will scare you for sure, but the plate in this case acts mainly as a memberanes. Consider the two actions.