Detailed Construction Process and Key Technical Points Analysis for Renovating Existing Building Exterior Walls with UHPC Panels

In facade renovation of existing buildings, how can UHPC panels achieve a leap in quality and efficiency by "giving old facades a brand-new look"? As an industry leader with 28 years of deep expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group leverages its full-chain technical strength to provide building renewal solutions that combine safety with aesthetic value.

As urban renewal accelerates, facade renovation of existing buildings faces the dual challenges of "enhancing appearance" and "ensuring structural safety". Traditional materials such as stone and aluminum panels suffer from heavy weight, complex installation, and insufficient durability, while ultra-high performance concrete (UHPC), with its ultra-high strength, excellent durability, and design flexibility, is becoming the preferred material for facade renovation. Drawing on Qinglong Group's practical experience from its annual production capacity of 600,000 square meters at its Nanning production base, this article details the construction process and key technical points of UHPC panels in facade renovation.

I. Full-Process Control of UHPC Panel Renovation Construction: A Standardized Path from Design to Acceptance

The use of UHPC panels in facade renovation of existing buildings requires closed-loop management across the entire process of "survey-design-production-installation-acceptance". In the preliminary survey stage, 3D laser scanning technology is used to obtain precise data of the building facade, which, combined with a structural safety assessment, determines the panel thickness (typically 20-30mm), anchoring scheme, and load parameters. In the design stage, BIM technology is applied for parametric modeling to achieve precise matching with the original building structure. Qinglong Group can provide integrated services from detailed design to production and processing at this stage, ensuring that component dimensional tolerances are controlled within ±2mm.

In the manufacturing stage, relying on patented technologies from Qinglong Group's national-level R&D center (58 patents in total), processes such as automated material distribution and steam curing are employed to ensure that UHPC panels achieve a compressive strength ≥150MPa and a flexural strength ≥30MPa. The installation stage innovatively adopts a "dry-hanging + flexible connection" technique, using specialized stainless steel connectors to elastically fix UHPC panels to the base wall, effectively resolving stress issues caused by building settlement and temperature deformation. The acceptance stage requires strict implementation of the "Ultra-High Performance Concrete (UHPC) Exterior Wall Panels" standard (T/CBMF171-2022), with comprehensive testing of indicators such as panel flatness and anchoring strength.

II. Key Technical Points: Solving the Four Core Challenges in Renovation Projects

1. Substrate Treatment Technology: To address the common problems of hollowing and cracking in existing building facades, Qinglong Group adopts a "surface sandblasting + interface agent penetration" process, increasing substrate adhesion by more than 40%. For unevenness defects in aged walls, error correction is achieved through a UHPC leveling layer, ensuring the flatness of the panel installation surface is ≤3mm/2m.

2. Lightweight-Safety Balance Technology: UHPC panels weigh only 1/4 of traditional stone (approximately 25-30kg/㎡). Combined with Qinglong's post-installed anchoring system (pull-out resistance ≥15kN), the load on the building structure can be greatly reduced. In a commercial complex renovation project in Guangzhou, this technology successfully achieved support-free installation of 2,000㎡ of UHPC panels, improving construction efficiency by 50%.

3. Integrated Waterproofing and Insulation Technology: By laminating an XPS insulation layer onto the back of UHPC panels, a three-in-one system of "decoration-insulation-waterproofing" is formed. The "Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC)" (JGJ/T423-2018), which Qinglong Group helped develop, specifies the construction process of this composite system, achieving a heat transfer coefficient ≤0.6W/(㎡·K) in an urban renewal project in Shenzhen.

4. Custom Shaped Component Technology: For the complex facades of existing buildings featuring curves and folded lines, Qinglong Group's GRP mold technology (reusable more than 50 times) enables high-precision shaped processing of UHPC panels. For example, in the Century Plaza renovation project on Nanjing East Road, translucent UHPC components achieved a light transmittance of 25%, becoming an iconic landmark of urban renewal.

As a national "Specialized, Refined, Distinctive, and Innovative" enterprise and a contributing unit to UHPC standard development, Qinglong Group has always upheld the mission of "creating aesthetically beautiful architecture", accumulating full-chain experience from material R&D to project implementation in the field of facade renovation for existing buildings. Whether it is the modern-style transformation of commercial complexes or the restoration of historic buildings, UHPC panels demonstrate comprehensive advantages that traditional materials can hardly match. Looking ahead, Qinglong will continue to integrate its 28 years of industry experience to provide designers and owners with more innovative UHPC/GRC/GRG/GRP system solutions, driving technological upgrading and quality improvement in the field of building renewal.