STUDY ON OPTIMUM EXCITATION WAVE IN GROUT QUALITY NONDESTRUCTIVE TESTING OF ROCK BOLT
锚杆锚固质量无损检测中的激发波研究

Numerical simulation and experimental testing are used to study wave propagation characteristics in grouted rock bolt. Both show that the waves which propagate in grouted rock bolt are guided waves and different frequencies have different wave velocities and attenuation characteristics. There is an optimum excitation signal which has smallest attenuation in the grouted structure and can propagate for longest distance in the grouted rock bolt. The optimum excitation signal for our experimental grouted structure which makes clearest end reflection is firstly found by numerical simulations. And then the experimental set-up and transducers are made and the experiment testing results agree well with the numerical simulation showing that the optimum excitation signal can increase greatly the penetration range of ultrasonic wave greatly.