Optimization for nonlinear stability

Abstract This paper is concerned with the optimal design of trusses to withstand nonlinear stability requirements. While basically a geometrically nonlinear problem, nonlinear stability accounts for large rotations and equilibrium in the deformed state in contrast to linear stability which results in a generalized eigenvalue problem and handles small rotations and equilibrium in the initial state. A two-phase iterative procedure of analysis and redesign is proposed for the nonlinear stability optimization problem. Phase one utilizes an incremental technique of analysis until the point of instability and phase two utilizes a recurrence relation based on optimality criteria for redesign. Examples are presented to illustrate the technique and weight savings involved.