Detailed Construction Process for Replacing a Single Damaged UHPC Curtain Wall Panel

UHPC curtain wall panels may suffer localized damage during use due to external impact or material aging, and single-panel replacement is a critical part of maintenance work. As Qinglong Group with 28 years of deep expertise in the UHPC field, we have drawn on maintenance experience from projects such as the Shenzhen Yirui Biotechnology Building and the Hainan International Convention and Exhibition Center to develop a four-step standardized process—inspection and assessment, removal preparation, new panel installation, and sealing treatment—ensuring that replacement work is safe and efficient while minimizing impact on building use. High-quality single-panel replacement should be completed within 24 hours, with seamless integration between new and old panels.

Inspection and assessment are the foundation of replacement work. The tapping method and infrared thermal imaging are used to determine the extent of damage and evaluate the degree to which surrounding panels are affected. During the maintenance of the Wuhan Han Show Theater, Qinglong Group used high-definition drone cameras for a comprehensive inspection, precisely locating damaged panels. The assessment covers the panel fixing condition, corrosion at connection points, and the degree of sealant aging, based on which a targeted plan is formulated. Minor cracks (width ≤0.3mm) can be repaired by grouting; when the damaged area exceeds 30% or structural safety is affected, full replacement is required. The assessment report must include a safety contingency plan to ensure the construction process is foolproof.

The removal preparation stage requires meticulous planning. Dedicated scaffolding is erected, with fall-protection nets and warning zones set up. In the roof maintenance of the Hainan International Convention and Exhibition Center, Qinglong Group developed a modular gondola system adapted to curved surfaces. Before removal, adjacent panels are temporarily reinforced, and specialized tools are used to loosen anchor bolts to avoid damaging surrounding structures. Damaged panels are slowly hoisted away, the substrate is cleaned, and the condition of embedded parts is checked. Substrate treatment includes rust removal and flatness correction, with deviations controlled within ±2mm. Thorough preparation is the guarantee of a smooth replacement.

New panel installation requires precise alignment. 3D laser scanning is used for positioning to ensure the new panels fit perfectly with the existing system. Qinglong Group uses BIM models to simulate the installation process and identify potential issues in advance. Adjustable hangers are used during installation, allowing ±5mm fine adjustment, with panel joint widths kept consistent with the existing system. Anchoring torque is strictly controlled: M12 bolts are torqued to 40-50N·m with an error of no more than ±5%. Initial adjustments are made immediately after installation to ensure panel surface flatness ≤3mm/2m. This refined installation makes the new panels blend seamlessly with the old system.

Sealing treatment is the key to waterproofing. Panel joints are cleaned down to a solid substrate, and a dedicated primer is applied. Qinglong Group prefers silicone sealant with a movement capability ≥25% and a service life of over 20 years. The sealant is applied at a thickness of 0.5 times the joint width, full and continuous. After application, it cures for 24 hours, during which exposure to rain or drastic temperature changes should be avoided. Final acceptance includes water tightness testing and visual inspection to ensure the replacement meets standards. Through this standardized process, UHPC curtain wall panel replacement is safe and reliable, extending the service life of the overall system.