The first-order inherent frequency decrease model of FRP considering damage evolution under random vibration load

Abstract

Based on the different failure modes of fiber-reinforced composites (FRP) under random vibration fatigue loading, these materials are categorized into brittle and ductile types. The study summarizes the damage evolution patterns of these two types of fiber-reinforced composites under random vibration fatigue loading, with matrix cracking and delamination being the primary damage modes. A new model is proposed to describe the degradation of natural frequency in fiber-reinforced composites under random vibration fatigue loading, quantitatively accounting for the effects of different damage modes on natural frequency reduction. The applicability of the model is validated using random vibration fatigue test data from two materials with different characteristics: 2D woven ceramic matrix C/SiC composites and 2D woven glass fiber resin-based composites. The results indicate that this model accurately describes the natural frequency degradation behavior of fiber-reinforced composites under random vibration fatigue loading.