Material Property Checks for MAT8

MAT8 only applies to 2D elements.

Material Requirements MAT8
Mathematical If n12*n21 = 1, an error termination will occur. 1
Semi-stability E1 < 0, E2 < 0, G12 < 0, G1,Z < 0, or G2,Z < 0 will result in an error termination.

PARAM,CHECKMAT,NO will disable this error.

Not all zeros If E1 = 0, E2 = 0 , and G12 = 0, an error termination will occur.

If E1 = 0, E2 = 0 , or G12 = 0, a warning is provided.

Consistency E1*n21 = E2*n12 is assured as only n12 is input.
Mathematical for composites After homogenization, if Det[G] = 0, an error termination will occur.

Comments

  1. By substitution of E1*n21 = E2*n12 into n12*n21 = 1, it can be expressed in terms of n12*n12*E2/E1 = 1.