Modeling Composite in NX NASTRAN as solid with Mat9 card

[aerohead56]

I am trying to perform a NX Solution 601 analysis of a composite laminate so that I can use the nonlinear contact features in Sol 601. I am however backed into a corner. If I model the laminate layer by layer the model is absolutely enormous to get a decent element aspect ratio (>10M DOF). I tried switching to a shell model at mid-plane with PCOMP cards, but Sol 601 does not support contact between edges and surfaces (modelling bolts as solids and the composite as plates). The only solution I can come up with is to use a few elements through the thickness and grouping the layers of composite and putting in equivalent MAT9 cards for each layer with the out of plane stiffness turned off. Does anyone know how to translate an ABD matrix into a MAT9 card? Maybe there is some other more straightforward way of going about this?

 

[aerohead56]

I think I figured it out after some research. Forget using MAT9. Am going to use MAT12 instead and calculate equivalent laminate properties using the matrix equations found in NASA Reference Publication 1351 "Basic Mechanics of Laminated Composite Plates". This gives a way of calculating Ex, Ey, Gxy and nu from the ABD matrices in case anyone is interested.

 

[stressebookllc]

Cool, but after you get the constants, why not use laminate elements?

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