Construction technology of vertical concealed laying of anti-seepage membrane for water cutoff curtain in the open-pit coal mine
(2.Xi’an Research Institute Co., Ltd., China Coal Technology and Engineering Group Corp., Xi’an, Shaanxi Province, China 710077)
(3.Shaanxi Key Laboratory of Coal Mine Water Hazard Prevention and Control Technology, Xi’an, Shaanxi Province, China 710077)
【Abstract】Anti-seepage membrane (HDPE geomembrane) is widely used in anti-seepage projects currently that mainly prevent pollution, leakage and diffusion, and its laying form is various. In an underground water cutoff curtain project of an open-pit coal mine in China, the anti-seepage membrane was laid vertically as the main body of the water cutoff curtain wall, and the largest concealed depth was about 50 m. Groove sections were connected by connection boxes. Through the grouting and backfilling process, the impermeability of the curtain wall was improved and the anti-seepage membrane was compacted. Finally, pumping test in the surrounding wells was used to verify the impermeability of the curtain wall. The results showed that the permeability coefficient of curtain wall of anti-seepage membranes was just 8.6 × 10−7 cm/s which met the design requirements. The curtain wall of anti-seepage membranes has the advantages of high efficiency, low cost, and environmental protection. The successful application of the anti-seepage membrane to this project provides a significant reference for other similar projects.
【Keywords】 open-pit coal mine; water cutoff curtain; anti-seepage membrane; vertical concealed laying; overlapping connection; surrounding well test;
(Translated by HAN R)
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