An Experimental Study Of Composite Geomembrane Leakage Detection Based On Resistivity Method

The vertical paving technology is to vertically lay the composite geomembrane in the stratum,and constructs the anti-seepage system through the impermeability of the geomembrane and the strength of the geotechnical medium.Recently,the technology has been widely used in engineering such as hydraulic structures,landfills,underground oil storage,and chemical dangerous goods disposal.However,vertical paving anti-seepage is a concealed project,which is limited by the construction process,material properties,and formation environment.It can cause leakage because of be partially damaged,resulting in safety hazards.Therefore,it is of great significance to accurately detect the damage location of the composite geomembrane and check the safety hazards of the vertical paving system,which is important for promoting the progress of water conservancy projects and environmental engineering.In this paper,the composite geomembrane leakage is studied because of the resistivity method.The numerical simulation and indoor model test method are mainly used to compare the variation and regularity of the resistivity profile in the low-resistance region when the geomembrane has different damage defects.The effectiveness of geomembrane leakage detection.This article mainly completes the following works:(1)Summarize the geophysical premise of composite geomembrane leakage detection and analyze the feasibility of using resistivity method for detection.The geothermal film disappears after the damage of the geomembrane because of has the characteristics of insulation and water blocking,,the dielectric resistivity of the rock and soil filled with groundwater decreases,and the resistivity difference occurs with the surrounding background field,so the resistivity profile can be lowered.The resistance is abnormal to determine whether the geomembrane is intact.(2)Studied the existing computing modules of pyGIMLI and BERT open source code,based on the Python language for secondary development,using this program to simulate the typical damage of geomembrane typical damage defects.According to the geophysical premise of geomembrane leakage detection,the typical damage characteristics of geomembrane are summarized and classified.The typical damage modes of geomembrane are mainly for point damage size,lateral damage size,vertical damage size and abnormal body.The effective embedding of the depth and the position between the two anomalous bodies was carried out.By comparing the simulation results of various parameters of different working conditions,the minimum size that can be detected under various working conditions is obtained,and the detection accuracy is accurate to the sub-meter level.(3)Design and manufacture the model device,electrode plate and other accessories according to the requirements of the model test to determine the test soil material preparation and resistivity measurement.The infiltration characteristics and diffusion laws of different defects in quartz sand are summarized.In the lateral damage condition,the water flow mainly spreads to the left and right sides along the damaged position.In the vertical damage defect condition,the water flow mainly moves along the damaged position to the two.Side and top diffusion;in the case of point breakage defects,the water flow spreads around the defect location.This feature is basically consistent with the dye diffusion map.