Construction Process and Key Points for Geomembrane Lining in Water Reservoirs

1. Pre-Construction Preparation

• Material Inspection:
  Verify geomembrane specifications (thickness, material type) and check for defects (punctures, tears). Prepare welding equipment and anchoring materials.

• Site Preparation:
  Clear the reservoir base of sharp objects, rocks, and roots. Grade and compact the subgrade to achieve ≥95% Proctor density with ≤3cm surface irregularities.

2. Geomembrane Installation

• Unrolling:
  Align geomembrane rolls parallel to the reservoir's long axis to minimize transverse seams. Maintain ≥1.5% slack for thermal contraction.

• Positioning:
  Use teams of 4-6 workers for large sections to prevent wrinkles. Allow 0.8-1.2m edge overlap for anchorage.

3. Welding Procedures

• Equipment Setup:
  Calibrate dual-track hot wedge welders to 250-300°C at 1.5-2.5m/min (for 1.5-2.0mm HDPE).

• Welding Execution:
  Achieve 25-40mm wide double seams with 10mm air channel. Continuous welding with ≤5% speed variation.

4. Seam Testing

• Visual Inspection:
  Reject seams with visible gaps, burns, or bead irregularities (>2mm height variation).

• Pressure Testing:
  Apply 0.25MPa air pressure to channel; maintain for 5min with ≤20% pressure drop.

5. Anchoring System

• Trench Specifications:
  Excavate 0.8m (D) × 0.4m (W) perimeter trench with 1:0.5 side slopes.

• Securement:
  Fold geomembrane into trench with 300mm overlap, backfill with CLSM (flowable fill) in 200mm lifts.

6. Quality Assurance

• In-Process QC:
  Document all welds with thermal images and pressure test logs.

• Final Inspection:
  Conduct 100% seam coverage with spark testing (≥15kV) and random destructive tests (ASTM D6392).

Title: "Geomembrane Reservoir Lining: Best Practices for Installation and Quality Control"

Key Metrics:
✔ Leak Prevention – Achieves ≤1L/ha/day permeability
✔ Installation Efficiency – 500-800m²/day crew output
✔ Durability – 30+ year service life with UV-stabilized formulations

Critical Tools:
▸ Infrared thermography for weld QC
▸ Spark tester (15-35kV) for hole detection
▸ Digital tensiometer for anchorage verification

Applications: Potable water storage, aquaculture ponds, industrial containment.