Construction Procedure for Replacing a Single Damaged UHPC Curtain Wall Panel: Standardized Operation and Safety Assurance Guide

Although UHPC curtain wall panels offer high durability, accidental impact, extreme environments, and other factors can still cause individual panel damage. A standardized replacement process is essential to ensuring the safety and aesthetics of the curtain wall system. Drawing on 28 years of UHPC/GRC/GRG/GRP after-sales maintenance experience, Qinglong Group has developed a full-process system of "preliminary assessment – on-site protection – precise removal – standardized installation – acceptance and handover" and has successfully completed damaged panel replacement for multiple projects including the Shenzhen Yirui Biotech Building and the Yangshengtang Pharmaceutical Hangzhou Industrial Park, achieving 99% compatibility with the original curtain wall after replacement.

I. Preliminary Preparation: Precise Matching of Assessment and Customization

Damage Assessment and Data Collection: A 3D laser scanner is used to obtain the dimensions and position data of the damaged panel and surrounding panels, analyze the cause of damage (such as impact or aging), and determine whether the surrounding structure is affected. When assessing a damaged panel for a project, Qinglong confirmed through BIM model comparison that only a single panel was damaged, with no need to disturb the overall structure. Custom New Panel: Based on the original design drawings and collected data, the replacement panel is precast in the factory to ensure its material, thickness, and color match the original panel (color difference ΔE≤2.0). Qinglong uses integrated coloring technology and pigments from the same batch as the original panel to guarantee visual consistency. Tool and Material Preparation: Specialized removal tools (diamond cutting saw, hydraulic pliers), installation tools (vacuum suction lifter, laser positioning instrument), sealant, waterproof gaskets, etc. are prepared, and all tools have passed safety inspections.

II. On-Site Protection and Old Panel Removal: Dual Control of Safety and Non-Destructiveness

On-Site Safety Protection: A protective canopy (load capacity ≥2kN/㎡) is installed below the damaged panel, and a warning zone is designated to keep unauthorized personnel out; for work at height, operators are equipped with full-body safety harnesses and working platforms are erected. Old Panel Removal: First, the sealant around the damaged panel is cut, and then the connector bolts are loosened. Hydraulic pliers are used to dismantle the panel in sections (to prevent it from falling as a whole); small damaged pieces are lowered by rope, while large panels are hoisted steadily to the ground with a vacuum suction lifter. Post-Removal Cleaning: Residual sealant and debris are removed from the surfaces of the connectors and keels, and the flatness of the keels is checked (tolerance ≤1mm/m); damaged keels are repaired promptly. In the Shenzhen project, Qinglong ground and cleaned the keels to ensure the installation base for the new panels met standards.

III. New Panel Installation and Sealing: Core Guarantees of Precision and Waterproofing

New Panel Hoisting: A vacuum suction lifter (suction force ≥1.5 times the panel weight) is used, together with guide ropes to control swinging, to hoist the new panel to the installation position, where a laser positioning instrument adjusts its levelness and verticality (tolerance ≤2mm/m). Connector Attachment: The new panel is precisely embedded into the connectors, and the connecting bolts are tightened with torque controlled at 40-50N·m to ensure a secure connection; elastic gaskets are set between the connectors and the panel to absorb vibration and deformation caused by thermal expansion and contraction. Sealing Treatment: Foam rods (with a diameter 1.2 times the joint width) are inserted into the joints, and neutral silicone sealant is injected to ensure the sealant joints are full and even. Qinglong uses specialized caulking tools to achieve a uniform joint width (5-8mm), seamlessly blending with the original curtain wall.

IV. Acceptance and Handover: Dual Guarantees of Quality and After-Sales Service

Installation Acceptance: The flatness, verticality, and joint width of the new panel are inspected, and a water spray test is conducted (no leakage over 30 consecutive minutes). Qinglong implements the "three-inspection system" — self-inspection, technical sampling inspection, and the owner's acceptance — all of which must pass before handover. Post-Installation Maintenance: The site is cleaned, and the new panel and surrounding panels are cleaned; a maintenance manual is provided, informing the client of the follow-up inspection cycle (re-inspection recommended after 6 months). Qinglong's after-sales system ensures that replaced panels receive the same warranty as the original panels; for example, the UHPC panels replaced in the Yangshengtang Pharmaceutical project carry a warranty of up to 10 years.

The key to replacing a single damaged UHPC curtain wall panel lies in precise matching and standardized operation, avoiding secondary impact on the overall curtain wall system. With professional tools, teams, and full-process control, Qinglong Group delivers a safe, efficient, and aesthetically pleasing replacement process, quickly restoring the curtain wall to its optimal condition and upholding the service philosophy of "striving for excellence."