【摘要】 钻探灌浆修补技术是填埋场防渗层漏洞修补问题。为了准确控制钻头到达卵石层且不能击穿防渗层,根据不同介质层振动信号响应不同来判断卵石层,波形时域分析方法能区分卵石层但对钻头要求较高,实际应用中存在局限。采用短时傅里叶(STFT)时频分析方法在牙钻条件下对三种介质模型中的振动信号进行分析,利用相应频带的能量突变点来区分卵石层,通过选用合适的窗函数和窗长提取不同介质层信号进行仿真。实验结果表明,STFT能有效区分卵石层和其它介质层,具有很高的准确率。更多还原

【Abstract】 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 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,the gravel layer is determined,and the waveform amplitude analysis method is used to reflect the characteristics of the signal in time domain.However,the result is affected by the conditions of the drill.STFT is adopted to analyze the vibration signal in different layers through appropriate choice of window functions and length,and by extracting different time-frequency features of the dielectric layers,using the corresponding energy band to distinguish gravel layer break point.The experimental results show that the STFT can distinguish the pebble layer from the other dielectric layers effectively with high accuracy.更多还原