在北京市东北旺农场南干渠上应用塑料薄膜防渗的生产性试验研究,始于六十年代初期,试验段用聚氯乙烯塑料薄膜衬砌渠道620米,衬砌面积4,000余平方米,埋藏在30～40厘米厚的保护土层下,至今已运行20年,仍保持良好的防渗作用。经取样试验,延伸率降低 The application of plastic film anti-seepage test on the south trunk canal of Dongbeiwang farm in Beijing began in the early 1960s. The test section was covered with PVC plastic film lining channel of 620 meters and lining area of ​​4,000 square meters and buried at 30 ~ 40 cm thick protective layer, has been running for 20 years, still maintain a good seepage effect. After the sampling test, the elongation decreased