Membrane elements are used to model surfaces where you might otherwise use shell elements. Membranes have no bending stiffness, and all the membrane's strength is in the plane of the surface. Membrane elements are suitable for modeling structures such as balloons and air bags. You assign membrane elements to a surface that has been meshed with either triangular or quadrilateral elements. See Membrane elements in the Abaqus Elements Guide for more information.
This task shows you how to use membrane elements.
Create a shell part in CATIA V5.
Apply a material to the part.
Create a mesh on the part. If necessary, use the Advanced Meshing Tools workbench.
Select Start>Analysis & Simulation>Nonlinear Structural Analysis from the menu bar to enter the Nonlinear Structural Analysis workbench. If necessary, set an empty analysis case or an analysis case that contains structural analysis procedures to be the current case.
Create a 2D property, and select the shell part as the support for the 2D property.
Create a 2D property enhancement.
From the 2D Property Enhancement dialog box that appears, do the following:
Select the 2D Property that you created in the previous step as the support.
Select Membrane for the type.
Specify the Section Poisson's Ratio. In membrane elements specifying the section Poisson's ratio defines the thickness behavior for both small- and large-displacement analysis. Do either of the following:
Toggle on Use analysis default to indicate that the change in thickness is based on the element material definition.
Toggle on Specify value, and enter a value for the Poisson's ratio to cause the shell thickness to change as a function of membrane strains. This value must be between –1.0 and 0.5. A value of 0.5 will enforce incompressible behavior, 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.
Click OK to close the 2D Property Enhancement dialog box.
Use the global or local element assignment tools to assign membrane elements to the mesh. See Modifying Global Element Assignments and Modifying Local Element Assignments for more information.