A thin sheet (thickness = 0.01 inch) of a 8" x 40" rectangular Steel (modulus of elasticity 30 Msi, Poisson ratio = 0.3) with a centered rectangular cutout 2"x10" needs to be subjected to an axial load, as shown. The strength of the material is 200 ksi and we desire to use a factor of safety of 1.5.
Part I: Direct Stiffness Method
1. Idealize the structure by discretize the domain with 3 springs taking advantage of symmetry.
2. Identify and label the active DOF on a sketch of the structural model shown
3. Determine the local stiffness matrix of each element based on the geometry and material properties.
4. Use connectivity information to directly assemble the global stiffness matrix and force vecto
5. Calculate the maximum load that the structure can sustain?
6. For this maximum load, how much does the thin sheet stretch?
7. Determine the internal forces in each spring section.