Topology optimization of geometrically and materially nonlinear structures

This paper presents the latest research on topology optimization of geometrically and materially nonlinear structures using a modified bi-directional evolutionary optimization (BESO) method. The complementary and external works are selected as the objective functions for nonlinear structures under a prescribed load and displacement respectively. The corresponding sensitivity numbers are derived using an adjoint method. The filtering scheme is used to obtain checkerboard-free and mesh-independent designs. Examples show considerable differences in topologies and stiffness of the optimal designs using linear and nonlinear finite element analyses. It is found that the design using nonlinear finite element analysis is always better than that using linear finite element analysis when large displacement is involved.