In order to achieve the dual purpose of obtaining materials on site and dredging the river, graded natural gravel is used as the filling material. However, under the high water level of the river, the embankment filled with gradual natural gravel will seep obviously, causing the embankment or quicksand pipeline to collapse. occur. In order to solve the above problems,
composite geomembrane is placed on the front and bottom of the dam. The weak permeability and filtering performance of the composite geomembrane can be used to prevent liquid leakage and gas volatilization on the embankment slope, and prevent the embankment slope from water erosion and wave impact.
The composite geomembrane consists of two layers of tissue and one layer of membrane. The weight per unit area of the upper and lower non-woven fabrics is 150 grams, the thickness of the PE film is 0.3 mm, and the total weight per unit area is 525 grams. The ecological flood control project used more than 2 million square meters of composite geomembrane.
Main construction techniques: 1) Clean the base surface, compact the slope and sand pad after reaching the flatness requirements, and apply the film after passing the acceptance;
2) Place the geomembrane of the slope from the top to the bottom, and place the horizontal mattress from the bottom of the slope. The placement position should be flat and moderately tight to accommodate a small amount of sagging, and two adjacent layers of geomembrane should be welded together;
3) Press the geomembrane of the slope foot with a plastic mesh stone net to avoid the impact of high-speed water flow and raise the diaphragm.
4) Fill the membrane with a certain thickness of soil sample to avoid damage to the geomembrane. The artificial lake covers an area of more than 2,000 acres, and the bottom of the lake uses geomembrane to prevent leakage.
Main construction technology:
1) Spread 50mm thick medium sand on the bottom of the lake to achieve the leveling effect, then spread the film and weld;
2) Spread a certain thickness of soil sample on the membrane to prevent damage to the geomembrane, and then compact it with a plastic mesh gabion.
