Specifying advanced properties for general shell stiffness sections

Specify the Section Poisson's ratio to define the shell thickness behavior. Specifying the section Poisson's ratio causes the shell thickness to change as a function of membrane strains.

• Toggle on Use analysis default to use the default value of 0.5, which will enforce incompressible behavior of the element for membrane strains.

• Toggle on Specify value, and enter a value for the Poisson's ratio. This value must be between −1.0 and 0.5. A value of 0.0 will enforce constant shell thickness, and a negative value will result in an increase in the shell thickness in response to tensile membrane strains.

Toggle on Density, and enter a value for the mass per unit surface area of the shell. The mass of the shell is determined from this density.

For most shell sections Abaqus will calculate the transverse shear stiffness values required in the element formulation. If desired, toggle on Specify values from the Transverse Shear Stiffnesses options to include nondefault transverse shear stiffness effects in the section definition, and enter values for $K_{11}$, the shear stiffness of the section in the first direction; $K_{12}$, the coupling term in the shear stiffness of the section; and $K_{22}$, the shear stiffness of the section in the second direction. If either value $K_{11}$ or $K_{22}$ is omitted or given as zero, the nonzero value will be used for both.

Click OK to save your changes and to close the general shell stiffness section editor.