Cementitious Waterproof Powder For Tunnel Negative Side

Material Advantages

1. Capillary crystallization and crack self‑healing: Active chemicals penetrate into concrete capillaries to form water‑insoluble crystals, sealing fine cracks up to 0.4 mm. It achieves self‑repair effect under water condition.
2. Suitable for negative‑side waterproofing: Works for both positive‑side and negative‑side application, resists reverse water pressure for basements and tunnels.
3. Integrated with concrete structure: No surface film formed. Resists blistering, peeling and aging. Its waterproof service life is consistent with concrete structure for permanent anti‑seepage performance.
4. Excellent substrate compatibility: Inorganic cement‑based material bonds firmly with concrete and cement mortar. Plastering, leveling and tile laying can be done directly on cured coating without extra primer treatment.
5. Eco‑friendly & non‑toxic: Inorganic powder without harmful substances, safe for drinking‑water tanks and water‑storage structures.
6. Applicable on damp substrate: Construction allowed on damp concrete surface, only standing water needs removing, complete drying is not required.
7. High hydro‑pressure & chemical resistance: High impermeability grade, resistant to underground water corrosion, stable under long‑term immersion, ideal for hydraulic and underground projects.
8. High rigid strength: Excellent 28‑day compressive and flexural strength, providing both waterproofing and structural protection.

Technical Indexes

Construction Methods

1. Substrate Preparation Concrete substrate shall be sound and solid. Remove laitance, oil stains and loose layers. Repair honeycombs, holes and wide cracks in advance. Keep substrate damp without standing water. Clean construction joints, post‑pouring belts and corners.
2. Mixing Mix powder with water according to specified water‑powder ratio, stir into homogeneous lump‑free slurry. Mix on‑demand for immediate use. Do not reuse slurry aged over 20 min by adding extra water.
3. Detail Reinforcement Apply one coat of cementitious capillary crystalline slurry as reinforcement for vulnerable areas such as construction joints, post‑pouring belts, pipe penetrations and cracks. Proceed to large‑area construction after full drying.
4. Main Surface Application Apply by brush or trowel in two coats. Apply the second coat only after the first coat is fully dried. Apply two coats in cross directions. Control consumption per unit area to guarantee coating thickness.
5. Curing (critical procedure) Start moisture curing right after initial setting of coating. Keep continuous water‑spray curing for no less than 72 hours. Avoid direct sun exposure, strong wind and frost. Improper curing will weaken crystallization activity.
6. Finished Product Protection Avoid impact and washing during curing period. Start subsequent plastering or backfilling work only after reaching design strength. Suitable construction temperature: 5‑35℃.