Systematic Waterproofing Solution for UHPC Panels Used on Roofs

Waterproofing treatment for UHPC panels in roofing applications is the core technology for ensuring building functionality and durability. Based on experience from large-scale projects such as the 120,000-square-meter wavy roof of the Hainan International Convention and Exhibition Center, Qinglong Group has developed a trinity waterproofing solution combining material modification, structural design, and joint treatment, enabling the UHPC roofing system to maintain excellent waterproofing performance even under rainstorm conditions, with a leakage rate below 0.01%.

The material's inherent waterproofing is the foundation. By controlling the porosity of UHPC below 2% and the water-binder ratio at ≤0.20, the matrix achieves an impermeability grade of P12 or above. Qinglong Group incorporates a silane-based hydrophobic agent into the formula (dosage of 0.3%-0.5%), achieving a surface contact angle of ≥110° and forming a "lotus leaf effect." Accelerated testing shows that treated UHPC panels have a water absorption rate of ≤1% after 7 days of immersion, far superior to the 5%-8% of ordinary concrete.

Structural design achieves active waterproofing. Following the rain screen principle, drainage cavities (width ≥20mm) and weep holes (spacing ≤1.5m) are installed. Panel joints are designed as pressure-equalized cavity structures, with inner sealant (movement capability ≥25%) combined with outer water guide plates to form multiple layers of protection. In projects in coastal areas, Qinglong Group uses CFD simulation to optimize drainage paths, keeping rainwater retention time within 3 minutes.

Joint treatment is a critical step. Special areas such as roof ridges and gutters are reinforced with metal flashing for enhanced sealing, with an overlap length of ≥150mm. Sealing collars are installed around penetrations, allowing ±5mm of movement. A regular maintenance regime ensures the long-term effectiveness of the waterproofing system, with a full inspection and maintenance recommended every 5 years.