Study on interface performance of GFRP-Balsa sandwich beam under fatigue load

This study focuses on the lightweight Balsa core composite sandwich structures suitable for engineering applications. The interface performance of GFRP-balsa sandwich beams was evaluated through static and fatigue tests, revealing the peeling life and process of mixed mode I-II interfaces. Additionally, the interface crack propagation and the mechanism of peeling failure under both static and fatigue loads were analyzed. The effects of parameters, such as span-to-depth ratio, stress ratio, and load level, on interface fatigue peeling performance were summarized. Based on the Paris theory, a mathematical model capable of describing the fatigue peeling process of such structures was established, and the peeling life of the interface crack was predicted.