EVA, The Ideal Waterproofing Product For Tunnel Project
Choose a right waterproofing membrane for tunnel project is vital. Contractors will consider the softness of the material, so that it can fit with the 1 lining surface, and will also consider the water resistance and weather resistance of the material. A waterproof membrane with strong comprehensive ability can be applied in tunnel construction.
During more than 10 years of research and development, Weidun company has continuously optimized its own EVA waterproof coils, and its products have the following advantages.
Water Resistance:
The material itself is impermeable, and heat-welded seams create a continuous barrier, minimizing leakage risks.
Flexibility:
Adapts well to substrate deformations and resists cracking, making it ideal for complex structures.
Chemical & UV Resistance:
Withstands exposure to acids, alkalis, and UV radiation, ensuring long-term durability.
Ease of Installation:
Lightweight, easy to cut, and quick to install using heat-welding techniques.
Eco-Friendly:
Non-toxic and environmentally safe.
Versatility:
Suitable for tunnels, roofs, basements, and more.
Where to by EVA Waterproofing Membrane?
Weidun® 008 EVA Waterproofing Membrane
Uses:
- Tunnel waterproofing projects
- Highway projects
Weidun® 008 EVA Waterproofing Membrane is a kind of anti-seepage material composed of high molecular polymer as the basic material, which can prevent liquid leakage and gas volatilization. Its a thin, flexible, and impermeable sheet made from a combination of ethylene and vinyl acetate polymers.
Waterproofing with EVA Membranes: Key Steps for Optimal Performance
I. Base Surface Preparation
The adhesion and effectiveness of an EVA waterproofing membrane depend heavily on proper base surface preparation. Since the waterproofing layer is installed between the primary lining (1st lining) and the secondary lining (2nd lining), ensuring a seamless bond between the membrane and the primary lining is critical.
Inspection & Repair
Begin by thoroughly inspecting the primary lining for cracks, unevenness, or defects. Remove loose rocks, oil stains, and debris. Repair cracks using grouting and fill honeycomb voids or cavities with mortar. Sharply protruding surfaces should be ground down to ensure a smooth base.
Flatness Control
The surface must meet a flatness tolerance of ≤5 mm (checked with a 2m straightedge). To achieve optimal adhesion, Weidun Company recommends spraying a cement mortar layer onto the primary lining. This step enhances surface uniformity and maximizes contact between the base and the EVA membrane.
II. EVA Membrane Installation
Weidun Company recommends two fixation methods: hook fasteners or heat-melt anchors. Below is a detailed guide for the heat-melt anchor approach:
Fixation
Secure the EVA membrane to the prepared base using heat-melt anchors (provided free of charge by Weidun Company). Position the anchors at designated intervals, pressing the membrane firmly against the primary lining.
Heat Welding
Use a heat-welding device (available for separate purchase) to melt the plastic heads of the anchors. This process fuses the membrane to the base, ensuring a tight, permanent bond.
III. Post-Installation Checks
Membrane Inspection
Verify that the membrane lies flat, free of wrinkles or damage. All seams must be fully welded and tested for airtightness (e.g., via air pressure tests).
Reinforcement Placement
If required by design, install a steel reinforcement mesh over the waterproofing layer. Maintain proper concrete cover thickness as specified.
Secondary Lining Construction
Once the waterproofing system is confirmed intact, proceed with the secondary lining using sprayed concrete. Apply concrete in layers, monitor thickness and compaction, and follow strict curing protocols to prevent cracks.
Why Choose Weidun’s Solution?
Our heat-melt anchor system ensures robust adhesion between the EVA membrane and the primary lining, eliminating voids and enhancing waterproofing reliability. Combined with meticulous base preparation and quality materials, this approach delivers a durable, leak-free structure ready for long-term service.
For more details on EVA membranes or customized technical support, contact Weidun Company today!
