What Is the Minimum Achievable Radius of Curvature for Single-Curvature GRC Panels?

The minimum curvature radius of single-curved GRC panels is a key indicator of a manufacturer's craftsmanship. Based on extensive project practice and accumulated data, Qinglong Group holds that the minimum curvature radius of high-quality single-curved GRC panels can reach 300mm, and can break through to 200mm with special techniques; this limit is jointly influenced by material performance, mold technology, and reinforcement measures.

Material performance is the fundamental constraint. The flexural toughness of GRC determines the minimum bending radius; the ultimate tensile strain of high-quality GRC can reach 0.3%. By optimizing the mix proportion, Qinglong Group raised the ultimate tensile strain of the cement mortar matrix to 0.25% and increased the fiber volume content to 3%, enabling 300mm curvature radius panels to pass bending tests without cracks. In a commercial center project in Shenzhen, mass production of cylindrical decorative panels with a 350mm curvature radius was successfully achieved, with panel thickness controlled at 15mm, satisfying both the styling requirements and structural safety.

Mold technology ensures forming precision. Small-curvature panels require high-precision mold support. Qinglong Group uses five-axis CNC machining to produce epoxy resin molds with surface accuracy of ±0.5mm. In the Yangshengtang Pharmaceutical Hangzhou Industrial Park project, to produce curved cornices with a 400mm curvature radius, a hot-press forming process was specially developed; by precisely controlling temperature (60±2℃) and pressure (0.5MPa), perfect forming of small-radius curved surfaces was ensured. The demolding system was specially designed with a multi-stage ejection mechanism to avoid damaging panels during mold release.

Reinforcement measures prevent cracking. Small-curvature areas are prone to stress concentration and require targeted reinforcement design. Qinglong Group adds radial stiffening ribs to the inner side of panels, with rib heights of 20-30mm and spacing of 150-200mm. Hybrid fiber reinforcement is also adopted: steel fibers (12mm long) and polypropylene fibers (6mm long) are mixed at a 7:3 ratio, significantly improving crack resistance. Through these technical measures, the curvature limit of single-curved GRC panels was successfully surpassed.