Investigation on guided wave characteristics of prestressed bolts based on mechanics of incremental deformations theory.

• A highly efficient recursive Legendre orthogonal polynomial approach for prestressed bolts is presented. • The applicability of the "Mechanics of Incremental Deformations" theory is verified by prestressed guided wave experiment. • The group velocity and attenuation on both sides of an intersection frequency exhibit completely opposite trends with the variation of prestress. The magnitude of prestress can reflect the degree of anchor bolt failure, but currently there are relatively limited theoretical research methods for the wave characteristics of prestressed bolts. For this reason, this paper establishes a viscoelastic bolt model with prestress based on the Mechanics of Incremental Deformations theory and the Kelvin-Voight viscoelastic theory, and proposes a recursive Legendre polynomial series method (RLPSM) to solve the longitudinal guided wave propagation characteristics in free bolts with prestress. The dispersion and attenuation curves of longitudinal guided waves in free bolts with various prestresses are given, and the influences of prestress on dispersion curves are analyzed. Meanwhile, the ultrasonic guided wave detection system of free bolts with prestress is established for laboratory research, and compared with the theoretical results. [ABSTRACT FROM AUTHOR]