Structural Design using Cellular Automata

Traditional parallel methods for structural design do not scale well. This paper discusses the application of massively scalable cellular automata (CA) techniques to structural design. There are two sets of CA rules, one used to propagate stresses and strains, and one to perform design analysis. These rules can be applied serially,periodically,or concurrently, and Jacobi or Gauss- Seidel style updating can be done. These options are compared with respect to convergence,speed, and stability

Bending of composite cylindrical shells with circular cutouts: Experimental validation

An experimental study of unstiffened graphite-epoxy cylindrical shells with cutouts subjected to bending load is presented. Two cylinders were tested: a classical laminated cylinder with constant-stiffness and a fiber-steered cylinder with variable stiffness in circumferential direction. Both cylinders were tested until collapse in displacement control. Displacements and strains were measured by displacement sensors, strain gauges, and two digital image correlation systems. Analysis of the test data indicates that the highest stressed area was the edges of the cutouts where local displacements created large compression strains. The experimental data were compared with progressive damage analysis results obtained with a finite element analysis that included measured geometrical imperfections. The research contributes to the knowledge of variable-stiffness composite structures and their applications in aircraft fuselages