How Large UHPC Panels Achieve a Continuous Stone-Grain Surface Effect: Research on Technical Paths and Process Innovation

In the field of contemporary architectural decoration, ultra-high performance concrete (UHPC) is becoming a key material for shaping the artistic expression of building skins, thanks to its outstanding mechanical properties and design plasticity. How to achieve continuous stone grain effects on the surface of large UHPC panels that rival natural stone is not only a technical challenge, but also a deep integration of material aesthetics and engineering practice. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group has successfully overcome this challenge through innovative technical approaches and process optimization, providing designers and owners with solutions that combine functionality and artistry.

The core of achieving continuous stone grain effects on the surface of large UHPC panels lies in the synergy between material mix proportions and texture forming technology. At the raw material selection stage, the Qinglong team adopted optimally graded quartz sand and special mineral admixtures, simulating the crystal structure of natural stone by adjusting particle gradation, while introducing a gradient colorant mixing process that achieves a color penetration depth of 5-8mm, avoiding the fading issues common to traditional surface spraying. In the texture forming stage, 3D scanning technology was innovatively combined with flexible molds: high-precision scanning of natural stone surfaces first generates a 1:1 digital texture model, and a silicone composite mold is then fabricated through CNC engraving to ensure precise reproduction of stone grain details. This process keeps the texture continuity error of a single UHPC panel within 0.2mm, perfectly presenting the natural texture of stone.

Process innovation provides key support for large-scale production. To address the texture continuity challenge of large UHPC panels (commonly sized 2.4m×6m), Qinglong developed a “segmented casting - seamless splicing” technology: a 0.5mm texture overlap allowance is reserved in the mold design, dedicated positioning pins ensure texture alignment between adjacent panels, and the company’s self-developed low-shrinkage concrete formula (28-day shrinkage rate ≤0.03%) effectively prevents texture breakage caused by material shrinkage. During production, a coordinated process of vacuum high-pressure casting and steam curing increases concrete density by 20%, with surface texture clarity reaching over 95%. This technology has been successfully applied to projects such as the Century Plaza renovation project on Nanjing East Road, where the stone grain effect of its translucent UHPC components won the Silver Award at the first UHPC Construction Engineering Innovation Awards.

A full-chain quality control system guarantees the durability of the stone grain effects. Qinglong has established full-process standards covering everything from raw material inspection to finished product installation: raw materials must pass 30 indicator tests upon arrival, ensuring that colorant weather resistance passes UVB-313 aging tests of 5,000 hours without obvious discoloration; during production, RFID chip traceability technology records key information such as casting time and curing parameters for each panel; during installation, 3D laser scanning positioning achieves millimeter-level precision control. In addition, Qinglong participated in formulating the industry standard “General Technical Conditions for Non-Load-Bearing Ultra-High Performance Concrete (UHPC) Components,” which makes explicit provisions on surface texture durability and promotes the standardization of industry technology. For more industry information: WeChat qlfsbl123

The application of continuous stone grain UHPC panels brings more possibilities to architectural design. In high-end commercial complex projects, they can achieve seamless integration with glass curtain walls and metal panels, creating rich facade layers through variations in stone grain texture; in cultural venue construction, UHPC’s plasticity allows the perfect combination of the solidity of traditional stone with the lightness of modern architecture. With an annual production capacity of 600,000 square meters and a service network covering the whole country, Qinglong has provided customized solutions for renowned real estate groups such as Poly and China Overseas, with products exported to overseas markets including Southeast Asia and Australia. As a national “Specialized, Refined, Distinctive, and Innovative” enterprise and a participant in industry standard formulation, Qinglong has always upheld the mission of “Creating Beautiful Architecture,” pushing material performance and artistic expression to new heights through technological innovation and empowering unlimited possibilities in building skin design.