Simply supported Sandwich Plate example 1

[Qshake]

I'm looking for design example of a simply supported sandwich plate subject to a uniform load normal to the face plates.

I've looked in many textbooks like Jones, Whitney, Ishai, Tsai, and Vasillev. Many have derivations but no complete examples.

I appreciate any suggestions.

Regards,
Qshake

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[TGund]

Try the "Sandwich Handbook" which you can download for free at the DIAB website (

http://www.diabgroup.com/americas/u_literature/u_lit_man.html).

If my memory serves, they have some plate examples near the end of the document. If that doesn't work, maybe check out "The Handbook of Sandwich Construction" by Dan Zenkert.

 

[YoungTurk]

I use the methods presented herein:

http://www.hexcel.com/NR/rdonlyres/...B3-7EFF685966D2/0/7586_HexWeb_Sand_Design.pdf

The document contains a complete example for each load case.

 

[RPstress]

Personally, I find the Zenkert a little on the academic side. Tom Bitzer's "Honeycomb Techonology: Materials, Design, Manufacturing, Applications and Testing" is a good bet.

Also, the Forest Products Laboratory (FPL) did a huge amount of research on sandwich structures decades ago, and an awful lot of their reports are available as downloads.

Having said that, most of the necessary stuff is adequately covered in the Diab and Hexcel references already given.

It depends a bit on what you mean by a "complete example".

 

[Qshake]

I've looked at the Hexcel and Diab examples and find that they use charts and graphical solutions.

I'm interested in the development of the extensional and flexibility stiffness matrices for a sandwich composed of cross ply laminates and the subsequent analysis to determine the maximum allowable load applied normal to the face. This should involve a classical plate theory solution but the maximum load I understand will be controlled by the failure modes of the first ply failure in the lamina or a variety of failures for the core material.

I hope this helps.

Regards,
Qshake

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[RPstress]

From the sound of it you want the fundamental orthotropic plate theory behind the simple analysis methods in the references. I don't remember even Zenkert going that basic. You probably want an actual elastician to answer this one. Have you checked out Timoshenko or Lekhnitskii?

 

[YoungTurk]

Perhaps "Principles of Composite Material Mechanics" by Gibson is closer to what you're looking for. Specifically, chapter 7 is "Analysis of Laminate" section 7.2 deals with "Theory of Laminated Beams in Pure Flexure". 7.8 is titled "Laminate Strength Analysis". This is the text I was taught from in college, but I've always found it TOO fundamental for practical application. Of course, I never wanted to spend the time required to go from fundamentals through to predicted failure, but it sounds like just what you're looking for.

 

[Qshake]

Sorry - forgot mention that I've been through Gibson...good info - just not enough of what I need.

Yes, RPStress and YoungTurk that is exactly what I'm doing.

Thanks for your suggestions.

Regards,
Qshake

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[MNLiaison]

The Hexcel paper is essentially based on MIL-HDBK-23 which summarizes many reports from the Forest Products Labratory. MIL-HDBK-23 is more in depth then the Hexcel document for sandwich structure.

You should be able use MIl-HDBK-23 to determine the loads on the face sheets and core. Then you can use MIL-HDBK-17 to analyze the laminate to determine failure points.

Mil-hdbk-17 vol III

http://assist.daps.dla.mil/quicksearch/basic_profile.cfm?ident_number=71716

IHS has Mil-HDBK-23 available.

http://www.ihserc.com

Best Regards

 

[PanelGuy]

If you want the full deal, "Analysis and Performance of Fiber Composites" by Broutman and Agarwal is great. As well, Bitzer wrote "Honeycomb Technolgy" which is the full guide of analysis with the Hexcel Technical Bulletin really being the Cliff Notes. Bitzer is "the man" when it comes to sandwhich panels, but Broutman really expands the laminate/laminae matrices. As well, if all else fails, reviewing the olds "Roarks Formulas" can get you there. I did not see right off if anyo of the had a "whole example"

Good luck!