A numerical study on lap joint fastener looseness detection using 2D simulated Lamb waves

This paper focuses on lap joint fastener looseness detection via ultrasonic guided waves features. The fundamental S0 Lamb mode interaction with a lap joint is simulated in a 2D plain strain finite element model using ABAQUD package. A uniform pressure representing the fastener load is applied in the lap area, and is changed gradually for sensitivity investigation. Results shows that the S0 mode with wavelength equals to one fourth of lap joint length has the largest transmission coefficient that increases monotonically with fastener load increase and can be used as a fastener looseness sensitive feature.