What Is the Construction Process for Replacing a Single Damaged UHPC Curtain Wall Panel? A Practical Guide to Safe and Efficient Replacement

Damaged single UHPC curtain wall panels must be replaced promptly to prevent the damage from spreading and creating safety hazards. A standardized construction process is the core of ensuring replacement quality and safety. Drawing on 28 years of curtain wall maintenance experience, Qinglong breaks down the key operational points of the entire process from initial preparation to final acceptance, ensuring the replacement work is efficient and orderly.

1. Initial Preparation and Safety Protection: Laying the Foundation for Replacement

Thorough preparation and strengthened safety control are required before replacement. First, survey the damage on site, recording the specifications, models, installation positions, and extent of damage of the components, and check them against the original design drawings to ensure the new components' parameters match. Custom-order matching UHPC curtain wall panels in advance; the new panels must pass strength testing (compressive strength ≥120MPa) with a surface flatness tolerance ≤2mm/m. Qinglong's custom components all comply with the "Ultra-High Performance Concrete (UHPC) Exterior Wall Panels" standard. Set up a safety protection system: install protective netting below the damaged components, designate warning zones around the area, provide scaffolding or aerial work platforms for work at height, and ensure workers hold valid certifications and wear full protective equipment.

2. Standardized Procedure for Removing Old Panels: Avoiding Secondary Damage

Old panel removal requires precise operation to prevent damage to surrounding components. Step one: remove the sealant by cutting along the panel joints with specialized cutting tools, avoiding violent tearing that could crack adjacent panels. Step two: remove the connectors by detaching the anchors and bolts in the order of "secondary first, primary later," using a torque wrench to control the removal force and prevent connector deformation or damage. Step three: hoist away the old panels—small components (weight ≤50kg) are lifted with an electric hoist, while large components use a truck crane; connect the lifting gear to the component precisely and lift slowly to avoid collisions. In the maintenance of the Shanghai Century Plaza project, Qinglong achieved zero-damage removal of old panels through this procedure. Finally, clean the installation base surface, removing residual debris and structural adhesive to ensure the base is flat and clean.

3. New Panel Installation and Adjustment: Precise Positioning with Attention to Detail

New panel installation must strictly follow precision requirements to ensure a secure fixing. Transport the new panels to the installation position and place them slowly using the same hoisting method as removal. Adjust the component positions so that panel levelness and verticality errors are ≤1mm, with even gaps to adjacent panels (standard gap 8-12mm). Install the connectors and tighten the bolts to the designed torque (M12 bolt torque ≥45N·m), ensuring the anchors fit tightly against the keel; Qinglong uses 3D laser positioning technology to improve installation accuracy. After adjustment, apply temporary fixing to prevent displacement during subsequent work, then carry out sealant application: use weather-resistant silicone sealant, with full and uniform sealant joints and a smooth, flat surface.

4. Acceptance and Follow-up Work: Ensuring Replacement Quality

Strict acceptance inspection and proper follow-up protection are required after installation. Appearance acceptance: check that the new panel surface is free of scratches and damage, panel joints are straight, and the sealant is free of bubbles and cracks. Performance testing: use pull-out tests to spot-check the load capacity of connectors, with single-point pull-out force ≥15kN, to ensure reliable connections. Clean the work site, remove protective facilities and construction tools, and clean and maintain the new panel surface. Establish replacement records documenting component information, construction dates, and acceptance results for traceability in later operation and maintenance. In the maintenance project of the Yangshengtang Pharmaceutical Hangzhou Industrial Park, Qinglong ensured a 100% pass rate for replaced components through a standardized acceptance process.