APPLICATION OF NEWTON MODIFIED BARRIER METHOD TO STRUCTURAL OPTIMIZATION

This paper presents the application of the Newton modified barrier met hod to obtain a minimum weight structure with constraints on displacem ents and minimum sizes. The solution to the problem is obtained via mi nimizing the modified barrier function (MBF) at each step by using the Newton method and updating Lagrange multipliers. The Lagrange multipl iers are updated by using the value of the constraints at the minimum of the MBF. Three truss problems with a different number of design var iables are solved. The convergence to the minimum weight design was fo und to be monotonic and the algorithm is potentially robust for solvin g problems with a large number of design variables.