DA11_Xia 2*c/(I0c/intop3(shell.DA11)+I2/intop3(shell.DD11)) "Equivalent extensional stiffness matrix, 11-component"
DA12_Xia intop3(shell.DA12/shell.DA11)*DA11_Xia "Equivalent extensional stiffness matrix, 12-component"
DA22_Xia intop3(shell.DA12)*DA12_Xia/intop3(shell.DA11)+lh/c*intop3((shell.DA11*shell.DA22-shell.DA12^2)/shell.DA11) "Equivalent extensional stiffness matrix, 22-component"
DA33_Xia c/lh*intop3(shell.DA33) "Equivalent extensional stiffness matrix, 33-component"
DD11_Xia c/lh*intop3(shell.DD11) "Equivalent bending stiffness matrix, 11-component"
DD12_Xia intop3(shell.DD12/shell.DD11)*DD11_Xia "Equivalent bending stiffness matrix, 12-component"
DD22_Xia 1/(2*c)*(I2*intop3(shell.DA22)+I0c*intop3(shell.DD22)) "Equivalent bending stiffness matrix, 22-component"
DD33_Xia lh/c*intop3(shell.DD33) "Equivalent bending stiffness matrix, 33-component"