In modern structural analysis, multi-layer composite materials are frequently encountered. These composites often appear as a complete shell structure, consisting of multiple layers stacked on top of each other. The angles, materials, and thicknesses of the each layer may vary. For the analysis of such composite materials, simulation software needs to provide relevant features, so users can input data based on the actual materials.
The WELSIM composite parameter input provides a simplified approach. This article will introduce the steps to define composites.
1.Create a new FEM project.
2.Add two material objects, named Glass and Plastic Film, respectively.
3.Double-click the Glass material object to enter editing mode. Set the initial density to 2.5e-6 kg/mm³, Young’s modulus to 70 GPa, Poisson’s ratio to 0.2, plastic yield stress to 80 MPa, hardening parameter to 500 MPa, and hardening exponent to 0.8. Add Orthotropic Brittle Failure properties with the default parameters set to 0.
4.Double-click the Plastic Film material object to enter editing mode. Set the initial density to 2.5e-6 kg/mm³, Young’s modulus to 100 MPa, Poisson’s ratio to 0.2, plastic yield stress to 10 MPa, hardening parameter to 20 MPa, and hardening exponent to 0.5. Add Orthotropic Brittle Failure properties with strain at the beginning of Tensile Failure set to 0.6, Maximum Tensile Strain set to 0.7, and the Maximum Tensile Strain for Element Deletion set to 0.8.
5.Add a plane shape to represent the shell structure. Users can also import a real shell structure. In the properties window, set the Structural Type to Multi-Layer Shell structure.
6.Once the Structural Type is set to Multi-Layer Shell, the table window is activated to edit layer data. This allows users to define the number of layers, angle, thickness, Z position, and materials for each layer. Here, a total of three layers are defined, with thicknesses of 1 mm, 0.5 mm, and 1 mm, and materials of Glass, Plastic Film, and Glass, respectively.
7.At this point, the multi-layer shell structure is defined and ready for subsequent analysis and computation. For example, an OpenRadioss input script can be generated to view the input layer data. As shown below, the material information and multi-layer shell structure properties are fully defined for the solver.
Conclusion
This blog demonstrates how to define a multi-layer shell structure and its associated material properties in WELSIM. This is the first step in composite material analysis. WELSIM makes it quick and easy to define multi-layer structures with its prowess. This feature has been implemented in the 2025R2 development version and will continue to be optimized in future versions.
WelSim and author are not directly related to the OpenRadioss development team and institution. The reference to OpenRadioss is only used here for technical blog and software usage references.