you may be intereted in an on-line calculator at "http://www.p-over-a.co.uk/toolbox/Huth.aspx" ... btw, nothing to do with me (not advertising, not selling, ...)

i've asked them if they use the (wrong) ATSM formula or Huth's original.

there are many other threads for Huth, a simple google for "Huth fastener flexibility" found lots of hits

Quando Omni Flunkus Moritati

Thanks, rb1957, but I would like to see the paper, get it translated by a German colleague, then give it some study. I have been presented with the formula in isolation; I would like to see more.

Both the ASTM and German version are calculated with this software:

http://www.espcomposites.com/software/software.htm...
use the eDistribution module

Unfortunately, it would probably violate copyright laws to post the papers.

I have the german paper and you don't even need to translate it (can just go by the equations). It seems pretty clear that the ASTM translation is wrong. It makes no physical sense for it to behave as stated in the ASTM version. The german version is physically consistent.

Brian
www.espcomposites.com

Thanks, Brian, but I would like to see more than the formulas. We have been directed by our customer to use the Huth formulation which has been included in one of the project documents. I would like to see the whole paper to assure myself that, in some concession cases, we are applying the formulation within its proper context.

StressMan2506...

The Heimo Huth Paper "Influence of Fastener Flexibility on the Prediction of Load Transfer and Fatigue Life for Multiple-Row Joints" is available in ASTM STP 927 Fatigue in Mechanically Fastened Composite and Metallic Joints (MAR 1985, ASTM PUB. CODE# [ISBN??] 04-927000-30). This book [ASTM STP 927] should be available thru ASTM or any large company or college/Uuniversity library... or any on-line technical-used-book reseller [found one for ~$73 on Barnes and Noble website]. I have a ratty copy of the book sitting on my desk from our corporate library.

NOTE. In general, the ASTM book appears to be fairly useful for understanding fatigue cracking originating from fastener installations...and some fatigue cracking prevention/retardation schemes... without diving deep into dozens [hundreds] of company [Boeing, McAir, Lockheed, etc] or DoD [AFWAL, etc] documents.

Regards, Wil Taylor

Trust - But Verify!

We believe to be true what we prefer to be true.

For those who believe, no proof is required; for those who cannot believe, no proof is possible.

as other posts above noted, the ASTM has an error in the Huth equation

Quando Omni Flunkus Moritati

rb1957...

So happens that my copy of the ASTM STP 927 book has a pen-ink correction to Huth's equation 1 with the notation "see original Huth paper"

Regards, Wil Taylor

Trust - But Verify!

We believe to be true what we prefer to be true.

For those who believe, no proof is required; for those who cannot believe, no proof is possible.

good to know ... only you didn't pass that along with the ASTM reference (so someone might read your post and think "well Will said to use the ASTM, and Will's someone i trust"

Quando Omni Flunkus Moritati

RB...

Most excellent point... and why I added my "pen-and-ink" comment. Hope hope folks refering to his thread in the future READ IT ALL.

Regards, Wil Taylor

Trust - But Verify!

We believe to be true what we prefer to be true.

For those who believe, no proof is required; for those who cannot believe, no proof is possible.

Following up on rb1957's comments about my on-line calculator at "http://www.p-over-a.co.uk/toolbox/Huth.aspx", the webpage has been updated to clearly show the formulation used, which is from Huth H, "Zum Einfluβ der Nietnachgiebigkeit mehrreihiger Nietverbindungen auf die Lastübertragungs und Lebensddauervorhersage" Bericht Nr. FB-172 (1984).

Jeff W
www.p-over-a.co.uk