Numerical parametric study on the propagation of longitudinal waves in GRFP bolts

This study investigates the propagation of longitudinal waves in Glass-Fiber-Reinforced Polymer (GFRP) rock bolts using numerical simulations. A two-dimensional axisymmetric model was used to represent the rock bolts. The simulations examined the effects of grout and rock on wave propagation, focusing on how these materials influence the temporal and spectral characteristics of the reflected longitudinal waves. The study also explored the impact of varying excitation frequencies on wave characteristics. Results show that the wave velocity increases with the elastic modulus of either grout or rock, with changes in the elastic modulus of grout only slightly affecting velocity, while changes in rock modulus significantly influence it. Additionally, wave velocity in the rock bolt decreased gradually as rock thickness increased.