Exploration and Analysis of the Minimum Curvature Radius Achievable for UHPC Single-Curved Panels

Breaking Material Limits, Reshaping the Curvilinear Aesthetics of Architecture—Technical Exploration and Engineering Practice of Curvature Radius in UHPC Single-Curved Panels

In contemporary architectural design, irregular curved surface elements are becoming the core language for shaping landmark buildings. As a new-type decorative building materials enterprise integrating full-chain services of detailed design, production and manufacturing, construction and installation, and after-sales maintenance, Qinglong Group (hereinafter referred to as Qinglong) has, drawing on 28 years of technical expertise in the fields of UHPC/GRC/GRG/GRP materials, continuously pushed the boundaries of material physical properties and processing techniques. This article focuses on the issue of curvature radius limits of UHPC single-curved panels, analyzing from three dimensions—material properties, process innovation, and engineering cases—how Qinglong transforms design concepts into architectural realities through technological innovation.

### UHPC Material Properties: Lightweight, High-Strength Foundation for Curved Forms

Ultra-High Performance Concrete (UHPC) is a fiber-reinforced composite material with a compressive strength of over 150MPa and a flexural strength exceeding 20MPa, along with excellent durability and toughness. Compared with traditional concrete, the high fluidity and early strength development characteristics of UHPC give it inherent advantages in forming irregular components. As a national high-tech enterprise, Qinglong has increased the fiber dispersion of UHPC by 30% through its independently developed mix optimization technology, providing the material foundation for forming single-curved panels with extremely small curvature radii. In actual projects, the thickness of Qinglong's UHPC single-curved panels can be controlled within 20-50mm, weighing only 1/4 of stone of the same volume, greatly reducing the load requirements on the building structure.

### Process Innovation: Full-Chain Breakthroughs from Mold Design to Forming Technology

Breakthroughs in curvature radius limits are inseparable from the support of precision manufacturing processes. Qinglong has established an industry-leading digital production line at its production base in Nanning, Guangxi, using CNC five-axis machining centers to manufacture molds with precision control up to ±0.5mm. For single-curved panel forming, Qinglong innovatively developed the "gradient pressurized casting process," which achieves uniform material distribution within the mold through a computer-controlled hydraulic system, effectively avoiding defects such as air bubbles and delamination that may occur in traditional casting. In a commercial complex project, Qinglong successfully achieved mass production of UHPC single-curved panels with a curvature radius of 300mm, with surface flatness error controlled within 2mm/m, far exceeding industry standards. In addition, the industry standard "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)" (Plan No. 2024-0232T-JC), formulated with Qinglong's participation, also provides technical specifications for the quality control of components with extremely small curvature radii.

### Engineering Practice: Translating Laboratory Data into Architectural Aesthetics

In the renovation project of Century Plaza on Nanjing East Road, the light-transmitting UHPC single-curved panel project undertaken by Qinglong achieved a flowing light-and-shadow effect on the building envelope through continuous curved surfaces with a curvature radius of 450mm; the project won the "Silver Award of the First UHPC Construction Engineering Innovation Award, AALBORG WHITE Cup." Meanwhile, in a cultural center project in Dongguan, through the synergy of parametric design and BIM technology, Qinglong perfectly integrated the 350mm curvature radius single-curved panels required by the designers with GRC decorative lines, satisfying structural safety requirements while presenting a delicate architectural texture. These cases confirm the technical feasibility of UHPC single-curved panels in curvature radius control and demonstrate Qinglong's industry-leading position as a UHPC manufacturer in realizing complex forms.

### Technical Boundaries and Future Prospects

Currently, the conventional curvature radius of UHPC single-curved panels in the industry is controlled at above 500mm, while Qinglong has pushed the limit for practical engineering applications down to 300mm through material formula optimization, improved mold precision, and forming process innovation. In the future, with the introduction of ultra-high-pressure forming technology and nanomaterial modification technology, this figure is expected to be further surpassed. As a Vice President Unit of the China GRC Association and a member unit of the International GRC Association, Qinglong has always upheld the mission of "creating beautiful architecture," committed to providing designers with broader creative space through technological innovation and building architectural works for owners that combine aesthetic value with structural safety. In the fields of UHPC/GRC/GRG/GRP materials, Qinglong will continue to leverage its full-chain service advantages to promote the innovative application of new architectural decorative materials in more high-end projects.