How to lay the HDPE geomembrane protective layer in anti-seepage construction?
The laying of HDPE geomembrane adopts the sequence of slope first and then pool bottom. When laying the film, do not pull it too tightly, leave a certain margin for local sinking and stretching. Horizontal joints shall not be on the slope surface and shall not be less than 1.5m from the foot of the slope. The longitudinal joints of adjacent sections shall not be on the same horizontal line and shall be staggered by more than 1m from each other. Do not drag or forcefully pull the geomembrane during transportation to avoid sharp objects from puncturing it. Temporary air ducts should be pre laid under the membrane to eliminate air underneath, ensuring that the geomembrane is tightly attached to the base layer. Construction personnel should wear soft soled rubber shoes or cloth shoes during construction operations, and pay attention to the impact of weather and temperature on the membrane.
The specific construction steps are as follows:
1) Cutting geomembrane: The actual measurement of the laying surface should be carried out to obtain accurate dimensions, and then cut according to the selected width and length of the HDPE geomembrane and the laying plan, considering the overlap width for welding. The fan-shaped area at the bottom corner of the pool should be cut reasonably to ensure that both the upper and lower ends are firmly anchored.
2) Detail enhancement treatment: Before laying the geomembrane, the internal and external corners, deformation joints and other details should be enhanced first. If necessary, double-layer HDPE geomembrane can be welded.
3) Slope laying: The direction of the film should be basically parallel to the slope line, and the film should be flat and straight to avoid wrinkles and ripples. The geomembrane should be anchored at the top of the pool to prevent it from falling and sliding downwards.
The protective layer on the slope is non-woven geotextile, and its laying speed should be consistent with the film laying speed to avoid human damage to the geotextile. The laying method of geotextile should be similar to that of geomembrane. Two pieces of geotextile should be aligned and overlapped, with a width of about 75mm according to the design requirements. They should be sewn together using a handheld sewing machine.
4) Bottom laying of the pool: Place the HDPE geomembrane on a flat base, smooth and moderately elastic, and closely adhere to the soil surface to avoid wrinkles and ripples. Two geomembranes should be aligned and overlapped, with a width of about 100mm according to the design requirements. The welding area should be kept clean.
Post time: Oct-07-2024