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Author Topic: Composite Strength, Laminate, Open Hole Tension (OHT) question  (Read 18633 times)


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Composite Strength, Laminate, Open Hole Tension (OHT) question
« on: September 24, 2008, 11:52:02 AM »
Does HyperSizer complete this calculation (and OHC after impact) when the material/layup is in the laminate form?

I have a stiffened panel that has a laminate selected for the analysis materials.  I used a laminate file because I need to use two materials in the same layup.

For each orthotropic material definition used, I have OHT and OHC after impact values defined.

When I check the laminate OHT and OHC calculations in the failure tab, I get "N/A Material" as a result.

Thanks for any help.

p.s.  I wasn't sure if this was answered in another thread.


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Re: Composite Strength, Laminate, Open Hole Tension (OHT) question
« Reply #1 on: September 25, 2008, 09:52:45 AM »
1. The OHC and OHT calculations do not appear in the Laminate Analysis form.  In addition, laminate based failure modes are also not available from this form.  The laminate analysis form only uses ply based failure modes.

2 In the sizing form, the laminate based allowables are based on percentage of plies in each direction.  Because the curves that contain these allowables are generally based on tests on non-hybrid laminates (all plies of the same materials), the % of plies in each direction for a hybrid laminate loses its meaning. 

When we implemented the laminate based failure method, it was decided that laminate based analysis would not be performed on hybrid laminates.  I believe that is what is causing the "N/A Material" message on the failure tab.