Geomembrane construction process flow

Zhoutou Reservoir Dam composite geomembrane seepage prevention adopts side-digging, side paving, bordering, edge protection

Base surface cleaning

The base surface must be cleaned up according to the design requirements. This is the key to ensure the anti-seepage effect. In particular, it must be thoroughly cleaned of sharp stones, tree roots and other debris, and the base surface must not be subject to local bumps. Use a rammer or spade to tighten it.

When laying the film, it must be laid up and down. Between the membrane and the membrane and between the membrane and the base surface should be flattened and tight, but it is not appropriate to pull the membrane too tightly. Generally, it should be slightly loose, but it cannot leave bubbles at the bottom of the membrane. Because the geomembrane is relatively thin and light, after being laid, it is very easy to be blown by the wind before the protective layer is laid. Therefore, the area of ​​the membrane to be coated should not be large, and it is better to cover the cover and cover the earth.

According to the information provided by the manufacturer, the width of the composite geomembrane is 1.0~1.9m. The width of the project is chosen to be 1.9m width to reduce the joint material. The joints are hot glued, glued, lapped, etc. The design of the project is glued and the seam width is 50mm.

If the geomembrane is found to be punctured or torn, it must be repaired with a geomembrane adhesive that is three times the damaged area.

Reliance on geomembrane 10cm thick protective layer of soil must be screened, does not allow particles larger than 6mm, or easy to pierce geomembrane. The protective layer earth material must be beaten and densified, and the dry bulk density is guaranteed to be above 1.5, and the sample should be sampled and tested at any time. When backfilling the protective layer and masonry stone protective surface, be sure to put it gently so as not to break the geomembrane. Below the block retaining surface, a 100mm thick gravel or gravel cushion should be installed to prevent the protection of the earthen material protective layer due to changes in water level, wind waves and other factors. The dry block stones shall be artificially paved and the stones shall be tightly embedded. The individual weight of the surface layer blocks shall be more than 48kg. All the voids shall be filled with small blocks of stone.

The requirements of the peripheral boundary treatment are to connect the composite geomembrane with the surrounding soil closely, block the seepage inlet, cut off the lateral leakage path, prevent the water seepage from entering the bottom surface of the geomembrane, form blisters, and burst the geomembrane when the reservoir level drops. . Therefore, it is necessary to excavate the cut-off water tank in the peripheral joint, and bury the geomembrane in the tank. Specific layout see the design.

Geomembrane features:

With a width of 6 meters, the widest composite membrane in China

High puncture resistance, high coefficient of friction

Good aging resistance, adapt to large ambient temperature range

Excellent anti-drainage performance

Applicable to water conservancy, chemical engineering, construction, transportation, subway, tunnel, garbage disposal plant and other projects

Main technical indicators: 400, 500, 600, 700, 800, 900, 1000 Remarks 0.25-0.35 0.3-0.5

Breaking strength KN/m 5 75 100, 120 140, 160 180

CBR bursting strength KN 11 15 19 22 25 28 30 vertical and horizontal

Tear strength KN 0.15 0.25 0.32 0.40 0.48 0.56 0.62