Discussion on Splicing Precision Requirements and Safeguard Measures for Curved GRC Shapes

[Exploring Joint Precision Requirements and Safeguard Measures for Curved GRC Shapes]

Breakthroughs in architectural aesthetics often begin with an extreme pursuit of detail. With their fluid lines and artistic expressiveness, curved GRC shapes have become the design choice for high-end projects such as landmark buildings and cultural venues. However, the joint precision of complex curved surfaces directly determines the integrity and safety of the building envelope, and its technical difficulty can rightly be called the “Mount Everest” of the GRC industry. As an industry leader with 28 years of full-chain UHPC/GRC/GRG/GRP experience, Qinglong Group will systematically analyze the precision control system for curved GRC shapes from three dimensions: technical standards, process innovation, and quality control.

1. Core Technical Indicators for Curved GRC Joint Precision

The joint precision of curved GRC shapes is not a single-dimensional parameter but a comprehensive system covering geometric dimensions, surface flatness, and structural safety. According to the Technical Standard for Building Application of Glass Fibre Reinforced Cement (GRC) (JGJ/T423-2018), the joint error of double-curved components must be controlled within ±2mm, that of single-curved components must not exceed ±3mm, and joint height differences must be ≤1mm to ensure overall visual continuity. For sharply curved sections with a radius ≤300mm, the curvature deviation must be ≤0.5° to avoid cracking caused by stress concentration. The General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components, which Qinglong Group participated in formulating, sets an even stricter standard for composite curved surfaces—a “three-coordinate inspection error ≤1.5mm/m”—an indicator that has reached the internationally advanced level.

2. Four Key Processes for Full-Process Precision Assurance

During the detailed design phase, Qinglong uses the Rhino+Grasshopper parametric design platform to transform the architect's creative models into producible component units, and performs virtual pre-assembly through BIM technology to eliminate spatial interference issues in advance. In production, the company pioneered a “modular mould system” using aerospace-grade aluminium profiles and curved master moulds machined by CNC machine tools, ensuring that the geometric precision error of the moulds themselves is ≤0.3mm/m. In view of the material characteristics of glass fibre reinforced concrete, Qinglong developed a “gradient curing process,” which combines constant-humidity static curing at 32°C with stepped cooling to keep component shrinkage deformation within 0.03%.

The combined “3D laser scanning + hoisting robot” technology in the installation phase serves as a “double safeguard” for precision control. Qinglong's independently developed intelligent installation system collects component spatial coordinates in real time and compares them with the BIM model, achieving sub-millimeter-level positioning through hydraulic fine-tuning devices. In the Nanjing East Road Century Plaza renovation project, this technology successfully achieved seamless jointing of 126 double-curved light-transmitting GRC components, with joint gap uniformity reaching 98%, winning the Silver Award of the AALBORG WHITE Cup UHPC Construction Engineering Innovation Award.

3. Quality Control System and Accumulated Industry Experience

As a national high-tech enterprise and a core unit in GRC standard formulation, Qinglong has established a full-process quality traceability system covering “design-production-installation.” Each GRC component is embedded with an RFID chip recording 28 key data items such as material mix ratios, curing parameters, and inspection results, enabling full traceability from raw materials to installation. In the Dongguan Women and Children's Activity Center project, this system raised the on-site jointing pass rate of more than 3,000 specially shaped GRC components to 99.7%, setting an industry record for precision control in projects of its kind.

Precision control of curved GRC shapes is both a technical challenge and a comprehensive test of materials, processes, and management. With 28 years of accumulated industry experience, Qinglong Group has developed a complete capability system ranging from millimeter-level precision control to kilometer-scale project management. From the double-curved curtain wall of the Guangzhou Opera House to the specially shaped decorations of the Kingdom Tower in Saudi Arabia, Qinglong has always maintained an attitude of “meticulousness and constant refinement,” providing solid technical support for the realization of architectural aesthetics worldwide. In the future, as UHPC/GRC composite technology continues to innovate, precision control of curved shapes will advance to even higher dimensions, injecting more possibilities into architectural art.