Manufacturer Pricing for Tunnel Waterproofing/Impermeable Geomembranes; Geomembranes for Wastewater Treatment; Double-Sided Textured (Studded) Geomembranes
Geomembranes—also known as HDPE geomembranes, impermeable membranes, PE membranes, or anti-seepage geomembranes—are impermeable materials manufactured from HDPE resin pellets. They are available in thicknesses ranging from 0.2 mm to 3.0 mm; products in the 1.0 mm to 3.0 mm range are commonly referred to in manufacturing as "boards" or "waterproofing boards" and offer properties such as impermeability and separation. Geomembranes are categorized by quality standards, including enterprise standards, national standards, virgin material grades, municipal construction grades, and ASTM (American) standards.
Due to their excellent impermeability, HDPE geomembranes are widely used in environmental protection and anti-seepage projects, including landfills, mining ash yards, waste residue treatment plants, reservoirs, municipal works, highways, fish ponds, biogas digesters, tailings ponds, water storage tanks, and artificial lakes.
Geomembrane Classifications:
1: GH-1 Geomembrane; 2: GH-2S Geomembrane; 3: GH-2T1 Geomembrane; 4: GH-2T2 Geomembrane; 5: GL-1 Geomembrane; 6: GL-2 Geomembrane.
Calculating Geomembrane Prices: Taking a 1.5 mm thick geomembrane as an example, the weight is 1,425 grams per square meter; the price can be calculated based on the cost per ton of the finished product. The formula involves multiplying the weight per unit area by the price per kilogram to determine the cost per square meter. Prices for polyethylene geomembranes of the same thickness may vary depending on quality requirements and the specific materials used.
Common Quality Defects in Geomembrane Installation
I. Geomembrane Damage
1 Phenomena:
The geomembrane exhibits defects such as bursting, punctures, abrasions, tears, rips, or aging.
2 Primary Causes:
(1) The geomembrane's thickness, mechanical properties, and durability fail to meet design specifications; packaging, transportation, and storage do not comply with regulatory requirements; or the product has exceeded its shelf life.
(2) The surface of the cushion layer beneath the geomembrane is uneven; the geomembrane is not laid flat, resulting in uneven stress distribution; or the geomembrane is damaged (punctured or burst) by rocks, debris, or rubble located beneath or above it.
(3) Sharp-edged debris remains on the site, or the geomembrane comes into contact with irregular, rigid materials.
3 Key Prevention and Remedial Measures:
(1) Use geomembranes that meet quality standards and ensure packaging, transportation, and storage comply with specifications.
(2) Install a cushion layer of gravel, crushed stone, or sand beneath the geomembrane; prior to laying the cushion, compact and smooth the base soil surface and remove any debris.
(3) Conduct a trial installation before full-scale laying; generally, proceed from one end to the other, laying the ends first followed by the middle section. The ends must be carefully laid and anchored with appropriate tension.
(4) Strengthen management to prevent construction-related damage and ensure timely backfilling for protection.
II. Poor Quality in Geomembrane Seaming or Patching; Water Seepage
1 Phenomena:
(1) Seams exhibit missed welds or heat damage; quality issues such as excessive tension, wrinkling, twisting, or improper overlapping occur during seaming and patching.(2) Geomembrane repairs are inadequate, resulting in areas where the bond has failed (debonding).
2 Primary causes:
(1) Seams are inspected solely by visual means.
(2) Water-soluble adhesive materials were used.
(3) Failure to properly prepare the uneven subgrade beneath the seam; sudden weather changes; insufficient slack (allowance) in the geomembrane.
3 Key prevention and remediation measures:
(1) Conduct on-site inspection of all welded seams.
(2) Use qualified adhesive materials.
(3) Prepare the subgrade properly before joining; perform joining under dry and favorable weather conditions whenever possible; visually inspect for missed seams or wrinkles after joining and verify with testing instruments; leave sufficient slack when laying the geomembrane.
III. Geomembrane loosening or sliding
1 Phenomena:
Movement, separation, or sagging occurs at longitudinal and transverse seams; on slopes, the geomembrane slides, slips downward, or suffers damage due to wrinkling.
2 Primary causes:
(1) Longitudinal and transverse connections are insecure, or the overlap length is insufficient.
(2) Unevenness at the seam or uneven stress distribution causes the seam to loosen.
(3) The upper end is unanchored or poorly anchored, leading to sliding under the combined influence of the weight of overlying fill material and the geomembrane's own weight.3 Key points for prevention and control measures:
(1) The overlap width of the geomembrane should be determined based on foundation conditions, ranging from 0.3 m to 0.9 m, and care should be taken to ensure the overlap area is not subjected to stress.
(2) If a sewn connection is used, the stitching thread and stitch spacing must ensure that the seam strength reaches at least 70% of the fabric's strength.
(3) During construction, it is essential to ensure that the foundation at the seam is level and firm, and that the anchoring at the ends is effective.
