What Is the Minimum Curvature Radius of a Single-Curved GRC Panel? Bending Limits and Qinglong Group's Process Breakthrough

The minimum curvature radius of single-curved GRC panels is jointly determined by the material's flexural performance, mold craftsmanship, and fiber reinforcement effectiveness; the industry's advanced level can reach R=300mm (at a panel thickness of 12mm). Through 28 years of technical accumulation, Qinglong Group, in the "Dongguan Grass Weaving" facade project of the Dongguan Women and Children's Activity Center, achieved mass production of ultra-small radius single-curved panels with R=280mm by optimizing the mix ratio (adding 0.3% polymer fiber), improving the demolding process (segmented demolding technology), and controlling the curing rate, with no cracks on panel surfaces and 100% fiber integrity. This breakthrough provides greater freedom for architectural expression, enabling GRC to simulate natural organic forms.

Material formulation is the foundation of small-radius bending. Reduce the maximum aggregate particle size to 0.3mm, add silica fume (20%) to fill micro-pores, and control the water-binder ratio at 0.32-0.35 to maintain workability. The flexible GRC formulation developed by Qinglong Group achieves an ultimate bending strain of ≥0.15%, three times that of ordinary formulations. In the Nanning Wuxiang China Resources MixC project, small-radius panels showed no damage after 50,000 fatigue tests.

Mold and demolding technology is key. High-elasticity silicone molds (tensile strength ≥8MPa) are used, with the demolding draft angle optimized to 1°. We invented an airbag-assisted demolding device to avoid stress concentration. In the Hainan theme park project, the demolding pass rate for curved panels with R=300mm reached 99.5%.

Quality control ensures mass production stability. Three-point bending tests are conducted on each batch, with the minimum curvature radius designed with a safety factor of 1.5. Qinglong Group's small-radius technology has expanded design boundaries.