| Popis: |
In this study, the contact quality of shotcrete-rock structures is studied using the impact-echo method (IE) to detect defects in shotcrete with a thickness of 10 and 20 cm. Numerical and experimental studies were conducted. Traditional frequency-domain analysis can only provide a qualitative judgment, but it fails to quantitatively estimate the severity of defect on the contact surface. Wavelet packet decomposition is used to analyze the signal to obtain the distribution of energy in each frequency band. The relative energy eigenvalues of the wavelet packet were calculated later, and the energy characteristic index of shotcrete with different thicknesses and bonding conditions was obtained. An interface quality evaluation approach based on energy was provided to quantitatively evaluate the contact quality at the interface of the shotcrete-rock structures. |
