Case study of anti-seepage engineering for river slope protection

　　The laying method of river anti-seepage membrane:

　　In large river channels, if the area is relatively large, it is still recommended that the construction party use anti-seepage membranes for anti-seepage at the bottom of the river, because the bottom of the river can be directly laid using overlapping anti-seepage membranes, which is relatively simple and fast, and the cost will be slightly lower.

　　However, it is recommended to use composite geomembranes for a series of anti-seepage measures for the slope protection on both sides of the river. The use of composite geomembranes can effectively prevent seepage by having geotextiles on both sides to protect the slope and protect the middle geomembrane.

　　The anti-seepage film should be carefully measured at the intersection of the slope or at the bend of the dam slope, and specially cut according to the actual situation to avoid the phenomenon of "hanging" or "bulging" after the construction of HDPE geomembrane. Cut the HDPE geomembrane into an inverted trapezoidal shape with top width and bottom width. This can make the anti-seepage film tightly adhere to the dam slope base.

　　At the intersection of the slope and bottom of the reservoir area with many blind ditches in design, HDPE geomembrane should be laid along the dam surface at a distance of 1.5 meters from the blind ditch, and then connected to the bottom membrane of the reservoir. The adjacent two frames should be welded before being pressed into the blind ditch.

　　When connecting the dam pipe with the geomembrane, the HDPE geomembrane is first cut into a trumpet shaped pipe sleeve according to the diameter of the dam pipe, and then the pipe sleeve is inserted into the dam pipe from large to small in order. After adjusting the position of the pipe sleeve, it can be temporarily fixed, and attention should be paid to the pipe sleeve not having any suspended parts. Weld the large and small sockets of the pipe sleeve onto the HDPE geomembrane and dam pipe, and reinforce them with stainless steel hoops. Combining quality and construction can effectively ensure the quality of the project.