Off-Axis Poisson Ratio interpretation

[nds88]

Hello,

I am working on some graduate level coursework and I am finding an off-axis Poisson ratio for a lamina is as high as 0.55 at a certain angle. I have a few references that show similar trends (Gibson's principles of composite material mechanics and this one here

https://ecm-academics.plymouth.ac.uk/jsummerscales/MATS347/MATS347A2 E-G-nu.htm).

I cant get away from the idea that Poisson ratio cant exceed 0.49... but yea I get it, its not an isotropic material. What's the interpretation of this? Is this expected?

 

[SWComposites]

Yes, it is expected.

 

[rb1957]

because its not isotropic

another day in paradise, or is paradise one day closer ?

 

[nds88]

Thanks for your replies, are there expected boundaries on these values then or are they just a direct result of calculated values in the lamina?

 

[WKTaylor]

Hey guys...

I wonder if this could also indicate some difficult to deal-with interlaminar forces that could require unique 'thru-reinforcement'???

Regards, Wil Taylor
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