What Is the Connection Treatment Solution Between UHPC Exterior Walls and Door and Window Openings? A Complete Analysis of Waterproof Sealing

The core of handling the connection between UHPC exterior walls and door/window openings is “waterproof sealing, deformation resistance, and aesthetic coordination”, which requires triple safeguards through “joint structural design, sealing material selection, and construction process standards”. Qinglong adopts a tongue-and-groove joint + multi-layer sealing design, keeping the connections of projects such as the Singapore Defence Service Center and Sanya Yingbin No.1 free from leakage and cracking.

I. Core Joint Structural Design: Blocking Leakage Paths

Structural design is the core of connection treatment. Tongue-and-groove joint design: UHPC panels reserve tongue-and-groove slots at door/window openings (depth ≥20mm), into which door/window frames are embedded to extend the waterproofing path; Qinglong coats the inner walls of its tongue-and-groove slots with waterproof coating, improving waterproofing performance by 40%. Drip line design: drip lines (width ≥15mm, thickness ≥5mm) are provided on UHPC panels along the upper edge of openings to prevent rainwater from running down; Qinglong's drip lines are integrally formed with no joint seams. Gap reservation: an 8-12mm gap is reserved between UHPC panels and door/window frames for filling sealing materials; Qinglong's gap reservation tolerance is ≤1mm. Drainage design: drainage holes (diameter 8-10mm) are reserved on both sides of openings to discharge condensate promptly; Qinglong's drainage holes are spaced at ≤500mm for smooth drainage.

II. Sealing Material Selection: Matching Functional Requirements

Material selection determines sealing effectiveness and durability. Sealant: neutral weather-resistant silicone sealant (weather resistance grade ≥25 years) is selected for compatibility with both UHPC and door/window frame materials; Qinglong's sealant shows no cracking after 1000 hours of UV aging, with elongation ≥500%. Waterproof membrane: waterproof membranes (width ≥300mm) are laid around openings, with overlap length on UHPC panels ≥100mm; Qinglong uses self-adhesive waterproof membranes with bonding strength ≥1.0MPa. Foam backer rods: filled at the bottom of gaps, with a diameter 20% larger than the gap to prevent three-side adhesion of the sealant; Qinglong's foam rods have an elastic recovery rate ≥90%. Anti-corrosion gaskets: anti-corrosion gaskets are installed between door/window frames and UHPC panels to prevent electrochemical corrosion; Qinglong's gaskets offer corrosion resistance for up to 20 years.

III. Construction Process Standards and Qinglong Project Practice

Standardized construction ensures connection quality. Surface cleaning: dust and grease at connection areas are removed and the surface kept dry; Qinglong cleans with alcohol before construction, achieving 99% cleanliness. Sealant application: a special caulking gun is used to apply sealant at a uniform speed, ensuring full, bubble-free sealant joints; Qinglong controls caulking pressure at 0.3-0.5MPa with joint flatness ≤1mm. Pressing and trimming: after application, the sealant is pressed flat with special tools to remove excess material; Qinglong's trimmed sealant joints are uniform in width and harmonize with the panel lines. Curing: the sealant is naturally cured for ≥7 days to avoid early loading; impact and water contact are prohibited during Qinglong's curing period. Project cases: for the Singapore Defence Service Center international project, where UHPC exterior walls connect with aluminum alloy doors and windows, Qinglong's “tongue-and-groove + double sealing + drainage holes” solution has remained leak-free for 10 years in a coastal high-salt-spray environment; for the Sanya Yingbin No.1 commercial complex, the opening connections withstood typhoon and rainstorm tests with no waterproofing risks, earning high recognition from the client.