Identification of effective elastic constants of composite plates based on a hybrid genetic algorithm

Vibration testing combined with a numerical method is a potential alternative approach for determining elastic constants of materials. To obtain better results, the numerical method based on a hybrid genetic algorithm is proposed. As verified from available data in the literature, the repeatability and accuracy of the proposed inverse determination method are confirmed, and it also shows that the concept of effective elastic constants is workable. The proposed method is applied successfully to determine the effective elastic constants of a woven composite plate and two PCBs. Moreover, a systematical two-step procedure is proposed to make up the problem of missing natural frequencies or natural frequencies with large errors due to the limitation in the measurement. Hence, the applicability of the present method to identify the effective elastic constants of inhomogeneous composite plates is demonstrated.