电法在垂直柔性防渗帷幕破损检测的应用

Electrical Method Used in Leakage Detection of Vertical Flexible Anti-seepage Curtain

为研究垂直柔性防渗帷幕的电学破损检测的可行性,该文通过系统分析垂直防渗帷幕的结构特征和漏洞特征,得出漏洞对其附近介质电势的影响,并分析漏洞检测方法,基于现场实验数据对模拟漏洞和实际漏洞结果进行验证,最后基于验证后的数据结果讨论了电法在垂直柔性防渗帷幕渗漏检测的可行性和影响因素,得出以下主要结论:该电法可以清晰地通过判断数据异常点(极大和极小值点)对漏洞位置进行定位,适用于垂直柔性防渗帷幕HDPE膜铺设过程的完整性检测,文章分析了检测传感器间距、供电电极到HDPE膜的距离、检测传感器到HDPE膜的距离等因素对检测结果的影响,但场地介质不均匀性和地形差异也可能影响检测结果,因此该方法无法完全克服上述不利因素。

In contaminated site remediation and management, leakage prevention of vertical flexible anti-seepage curtain is of critical importance. This paper intended to apply the electrical scanning imaging method（ESIM） to breakage detection of vertical flexible anti-seepage membrane, focusing on investigation of the impacts of leakage on the media potential near the leakage loophole. On the basis of an in-situ leakage detection at a solid-waste landfill site, the experimental simulation and actual leakages data were obtained and verified; as a result, the electrical method can be used to clearly locate the loophole position by means of the anomaly judgment data（maxima and minima）, and was suitable for the integrity testing in vertical flexible curtain HDPE liner laying process. In addition, the influence of the factors such as sensor spacing, the distance from the electrode to membrane and the distance between the sensor and membrane were analyzed; however, the inhomogeneity of ground medium and topographic differences may affect precision of the test results, and still the defects of the method had not been completely overcome.