The Analysis of STFT to the Medium Layer´s Vibration Signal and its Application in the Technology of Leaks Repair in the Landfill

Drilling grouting repair technology is an important direction of development in landfill liner leakage detection and repair, the difficulty and keystone of this technology is that how to detect the gravel layer, in order to avoid damaging the HDPE membrane. According to the different responses of the vibration signal in the different media of landfill site, using the short-time Fourier transform (STFT) to analyze the vibration signal and determine the gravel layer. The experimental results show that STFT can reflect the frequency characteristics of the vibration signals in different dielectric layers intuitively and clearly, and distinguish the gravel layer from waste layer.