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Re: Failure modes *PIC*
By:JohnAbercrombie
Date: 5/30/2016, 9:16 pm
In Response To: Failure modes (Nick Schade - Guillemot Kayaks)

That small dent is a compression failure. This results in a transfer of load to the other side resulting in a tension failure. If the exterior is strong enough to prevent the dent, the tension failure might not happen.

Point impacts that create dents can result in very high loads with a lot of energy concentrated in one area. Just because there is less evident damage on the compression side, does not mean the tension side is weaker.

More reading:
http://www.oceanica.ufrj.br/ocean/cursosead/materiaiscompositos/compositematerials/r_failure_modes.pdf

Thanks for that reference.
I don't see how an impact - force applied at right angles to the panel - results in a compression failure. Doesn't the impacting object (rock/hammer) tend to stretch/elongate the glass on the panel face? Wouldn't that be a tension failure?

Classic compression failures are usually illustrated with the force applied along the long axis of the panel/beam, as in the reference suggested above.

None of those modes look similar to an impact, to me.

Messages In This Thread

Strip: Fiberglassing the seam *PIC*
Fred Brown -- 5/29/2016, 6:02 pm
Re: Strip: Fiberglassing the seam
Rod Tait -- 5/29/2016, 9:07 pm
Re: Strip: Fiberglassing the seam
Fred Brown -- 5/29/2016, 10:07 pm
Re: Strip: Fiberglassing the seam
JohnAbercrombie -- 5/29/2016, 11:10 pm
Re: Strip: Fiberglassing the seam
Fred Brown -- 5/30/2016, 6:46 am
Re: Strip: Fiberglassing the seam - bias cut is al
Ian Johnson -- 6/1/2016, 7:46 am
Re: Strip: Fiberglassing the seam - bias cut is al
Bill Hamm -- 6/2/2016, 12:49 am
Re: Strip: Fiberglassing the seam - bias cut is al
ian johnson -- 6/2/2016, 6:22 pm
Re: Strip: Fiberglassing the seam - bias cut is al
Sam McFadden -- 6/2/2016, 8:23 pm
Re: Strip: Fiberglassing the seam - bias cut is al
Bill Hamm -- 6/3/2016, 7:37 am
Re: Strip: Fiberglassing the seam - bias cut is al
Ian johnson -- 6/5/2016, 5:46 am
Re: Strip: Fiberglassing the seam
Brian Nystrom -- 5/30/2016, 4:02 pm
Re: Strip: Fiberglassing the seam
Nick Schade - Guillemot Kayaks -- 5/30/2016, 4:32 pm
Re: Strip: Fiberglassing the seam
Marc Donnelly -- 5/29/2016, 10:18 pm
Re: Strip: Fiberglassing the seam
Craig -- 5/30/2016, 6:06 am
Re: Strip: Fiberglassing the seam
Fred Brown -- 5/30/2016, 6:51 am
Re: Strip: Fiberglassing the seam
Bill Hamm -- 5/31/2016, 12:46 am
Re: Strip: Fiberglassing the seam
Rob Macks/Laughing Loon CC&K -- 5/30/2016, 10:19 am
Re: Strip: Fiberglassing the seam
JohnAbercrombie -- 5/30/2016, 11:43 am
Re: Strip: Fiberglassing the seam
Rob Macks/Laughing Loon CC&K -- 5/30/2016, 12:07 pm
Re: Strip: Fiberglassing the seam
JohnAbercrombie -- 5/30/2016, 12:17 pm
Re: Strip: Fiberglassing the seam
Rob Macks/Laughing Loon CC&K -- 5/30/2016, 1:45 pm
Re: Strip: Fiberglassing the seam
JohnAbercrombie -- 5/30/2016, 2:09 pm
Re: Strip: Fiberglassing the seam
JohnAbercrombie -- 5/30/2016, 2:16 pm
Re: Strip: Fiberglassing the seam
Rob Macks/Laughing Loon CC&K -- 5/30/2016, 2:27 pm
Failure modes
Nick Schade - Guillemot Kayaks -- 5/30/2016, 4:04 pm
Re: Failure modes
Rob Macks/Laughing Loon CC&K -- 5/30/2016, 5:08 pm
Re: Failure modes
Nick Schade - Guillemot Kayaks -- 5/30/2016, 7:27 pm
Re: Failure modes *PIC*
JohnAbercrombie -- 5/30/2016, 9:16 pm
Re: Failure modes
Bill Hamm -- 5/31/2016, 12:54 am
Re: Failure modes
Nick Schade - Guillemot Kayaks -- 5/31/2016, 11:07 am
Re: Failure modes
Marc Upchurch -- 5/31/2016, 12:14 pm
West System failure tests for strips
Mike Bielski -- 5/31/2016, 11:35 pm
Re: Strip: Fiberglassing the seam
Sam McFadden -- 5/31/2016, 2:06 pm
Re: Strip: Fiberglassing the seam
Marc Upchurch -- 5/31/2016, 3:38 pm
Re: Strip: Fiberglassing the seam
Nick Schade - Guillemot Kayaks -- 5/31/2016, 4:26 pm
Re: Strip: Fiberglassing the seam
Sam McFadden -- 5/31/2016, 5:01 pm
Re: Strip: Fiberglassing the seam
Bill Hamm -- 6/1/2016, 12:42 am
Re: Strip: Fiberglassing the seam
Bill Hamm -- 5/31/2016, 12:50 am
Re: Strip: Fiberglassing the seam
Fred Brown -- 5/30/2016, 11:59 am
Re: Strip: Fiberglassing the seam
Fred Brown -- 5/30/2016, 7:35 pm
Re: Strip: Fiberglassing the seam *PIC*
Etienne Muller -- 5/31/2016, 3:18 am
Re: Strip: Fiberglassing the seam
Bill Hamm -- 6/1/2016, 12:45 am