Detailed Construction Workflow for Retrofitting Existing Building Facades with UHPC Panels: Steps, Key Technical Points, and Precautions

Detailed Construction Process for Retrofitting Existing Building Facades with UHPC Panels: Steps, Technical Points, and Precautions

With the acceleration of urban renewal, facade renovation of existing buildings has become an important issue in improving building safety and aesthetics. Ultra-high performance concrete (UHPC), with its ultra-high strength, excellent durability, and rich design expressiveness, demonstrates significant advantages in the field of curtain wall renovation. As an industry-leading enterprise with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group has drawn on hundreds of engineering projects to develop a scientific and efficient construction system for UHPC panel facade renovation, providing designers and owners with a one-stop solution from detailed design to after-sales maintenance.

I. Preliminary Preparation: The Foundation of UHPC Panel Renovation Projects

The core of facade renovation of existing buildings lies in safety assessment and precise adaptation. Before construction, the original structure must be comprehensively inspected, with a focus on verifying the strength and flatness of the base wall and the load-bearing capacity of anchoring points. Three-dimensional laser scanning technology is used to build a digital model of the building, providing data support for the customized production of UHPC panels. Relying on the BIM detailed design system developed by its provincial-level engineering technology center, Qinglong Group achieves integrated operations covering component splitting, load calculation, and installation simulation, ensuring that every UHPC panel (typically 8-15mm thick, weighing only 1/4 of traditional stone) perfectly matches the building structure. During the material preparation stage, incoming inspection must be strictly enforced, with close attention to the bending strength of UHPC panels (≥20MPa), elastic modulus, and surface texture treatment, while dedicated installation connectors are prefabricated according to design requirements.

II. Core Construction Process: Standardized Operations for UHPC Panel Installation

1. Base Treatment and Measurement and Setting Out: Remove attachments from the original wall, repair cracks and depressions, and apply a dedicated bonding agent to enhance base adhesion. Precise setting out is performed based on the BIM model, with datum control lines and elevation control points established and errors kept within ±2mm.

2. Keel System Installation: Based on load calculation results, hot-dip galvanized steel keels or aluminum alloy keels are selected and reliably connected to the original structure with chemical anchor bolts. Qinglong Group's original "double anti-corrosion process" ensures the durability of keels in humid environments, and joint treatment complies with the requirements of the "Ultra-High Performance Concrete (UHPC) Exterior Wall Panels" standard T/CBMF171-2022.

3. UHPC Panel Hoisting and Fixing: Dedicated vacuum suction lifting equipment is used, and panels are installed one by one in numbered order. Panel joints are controlled at 5-10mm and filled with elastic sealant, while drainage channels are provided to prevent rainwater leakage. Qinglong's patented adjustable connectors enable three-dimensional fine adjustment, ensuring panel surface flatness errors of ≤3mm/2m.

4. Surface Treatment and Acceptance: After installation, cleaning and protective treatment are carried out, and joints are finished with sealant. The acceptance stage requires focused inspection of anchoring strength, joint uniformity, and overall appearance, with comprehensive testing conducted in accordance with the "Technical Standard for Architectural Application of Glass Fiber Reinforced Cement (GRC)" JGJ/T423-2018.

III. Technical Points and Risk Prevention and Control: Key Aspects for Ensuring Project Quality

UHPC panel facade renovation requires particular attention to the coordinated load-bearing of new and old structures. Qinglong's technical team optimizes anchoring solutions using finite element analysis software and adopts flexible connection designs in areas with high seismic fortification intensity to release thermal stress and seismic loads. To address the uneven base surfaces commonly found in existing buildings, an innovative combined process of "local leveling + adjustable brackets" is adopted to prevent panel cracking caused by uneven loading. Ambient temperature is strictly controlled during construction; when it falls below 5°C, winter construction measures are taken to ensure the stable performance of UHPC panels and sealant.

IV. Qinglong's Full-Chain Service Advantages: Professional Support from Design to Maintenance

As a national high-tech enterprise and a participating unit in UHPC standard development, Qinglong Group provides full-process services covering detailed design, manufacturing, construction and installation, and after-sales maintenance. Its Guangxi production base has an annual capacity of 600,000 square meters and uses automated production lines to ensure stable product quality; more than 20 offices across the country enable rapid response and cooperation with project parties to solve construction challenges. To meet different customer needs, Qinglong offers innovative solutions such as UHPC and GRC composite curtain wall systems and translucent concrete decorative components, which have been successfully applied in benchmark projects such as the Century Plaza renovation on Nanjing East Road and the Dongguan Women and Children's Activity Center, with products exported to overseas markets such as Southeast Asia and Australia.

Switching existing building facades to UHPC panels is a systematic project that requires the organic combination of material performance, detailed design, and construction techniques. Backed by 28 years of industry experience, Qinglong Group carries its quality philosophy of "meticulousness and the pursuit of excellence" throughout the entire project cycle, providing safe, durable, beautiful, and cost-effective UHPC solutions for urban renewal projects and helping to realize its corporate mission of "creating beautiful architecture."