Structural Optimization of Reinforcement considering the Fatigue Life in a Dynamic System

摘要

In this paper a new topology optimization method that can consider fatigue life is presented. The fatigue life is the time until the fracture of the structure occurs. To estimate the fatigue life in the frequency domain, a method that consists of the power spectrum density (PSD) function and the probability density function (PDF) is used and it is called a narrow band solution. The narrow band solution is the general method for the narrow band frequency region. In this research, the design domain consists of two layers and optimization is conducted in the top layer (the bottom layer is excluded from the optimization procedure). This is because the design of the reinforcement is to be kept as in the original structure. Moreover because this method is also related to stress based topology optimization, the qp-relaxation and p-norm method are used to overcome the singularity problem and local behaviour.