Hooman Kargar - Member of Center of Advanced Systems and Technologies (CAST), School of Mechanical Engineering, Tehran University, ۱۴۱۷۴۶۶۱۹۱, Tehran, Iran;
Aghil Yousefi-Koma - Head of Center of Advanced Systems and Technologies (CAST), School of Mechanical Engineering, Tehran University, ۱۴۱۷۴۶۶۱۹۱, Tehran, Iran;

The loosening of the bolt joint assembly is a serious incident. It has the potential to cause catastrophic failure in a wide range of industrial devices, especially in the automotive and aerospace industries. The primary purpose of this article is to study at bolt loosening in bolt-connected structures. To accomplish so, a ۲D model of the lap joint specimen and piezoelectric transducers are simulated using ABAQUS FE software. Several simulations are carried out for different overlap area length, bolt pressures, excitation voltages and contact frictions. The effects of various overlap lengths on wave transmission through bolted lap joints are first explored, and the optimal indication for this investigation is chosen. The results revealed that the S۰ mode of lamb waves is the greatest indication for this investigation. The effect of bolt pressure on wave transmission through bolted lap joints is then studied. The results show that due to existing waves and non-ideal contact, transmitted waves through a bolted lap joint are disordered at low pressures. Increased pressure improves plate contact, allowing waves to pass through the lap joint more efficiently. After that, the influence of stimulation voltages on wave transmission in particular pressure, is studied. The findings reveal that increasing the excitation voltage only affects the receiving signal's amplitude, not its arrival time. Finally, the influence of contact friction on wave transmission is examined at various pressures. Increased contact friction lowers signal arrival time while boosting peak to peak amplitude, according to the findings.

bolt loosening, Lamb waves, ABAQUS FE, Bolted lap joints.