What Are the Jointing Precision Requirements for Curved GRC Shapes? Qinglong Group's 28-Year Precision Control System for Curved Surface Construction

The jointing precision of curved GRC shapes is a core indicator of construction quality, directly determining the final visual effect and structural safety. As an industry leader with 28 years of deep expertise in the GRC field, Qinglong Group—drawing on practical experience from national-level landmark projects such as the "Red Lantern" double-curved curtain wall of the Wuhan Han Show Theatre and the wave-shaped roof of the Hainan International Convention and Exhibition Center—has quantified the jointing precision standards for curved GRC as: joint width deviation ≤ ±1.5mm, height difference between adjacent panels ≤ 2mm, and overall curved surface smoothness error ≤ 3mm/2m. In the double-curved shape project of Nanning Wuxiang China Resources MixC, through total station 3D setting-out and an adjustable connection system, we controlled the installation precision of 287 irregular double-curved panels within ±1.2mm, achieving a high-fidelity reproduction of the design shape.

Precision control must start at the design source. Qinglong Group uses the Rhino+Grasshopper parametric design platform to optimize the segmentation of complex curved surfaces, ensuring gentle curvature changes for each panel. Finite element analysis is used to predict installation stresses, with control points densified in stress concentration areas. In the wave-shaped project of the Shenzhen Yirui Biotechnology Building, through digital pre-assembly technology, we identified and corrected 23 potential jointing conflict points in advance, avoiding on-site adjustments at the source.

Refined management of the construction process is the key to precision assurance. We introduced surveying robots to establish a high-precision control network, with setting-out errors ≤ ±1mm. A 3D adjustable bracket system is adopted, supporting horizontal, vertical, and in-out three-directional adjustment, with an adjustment range of up to ±10mm. Installation follows the standardized process of "measuring and positioning - preliminary fixing - fine adjustment and correction - final locking," using a laser level to monitor panel surface flatness in real time. In the 120,000-square-meter roof project of the Hainan International Convention and Exhibition Center, through this refined construction approach, the single-day installation efficiency reached 500 square meters with a 100% pass rate.

Precision control of special locations requires particular attention. At internal and external corner transitions, we use dedicated positioning fixtures to ensure angular deviation ≤ 0.5°; in areas with high requirements for curved surface continuity, the density of measurement control points is increased to no fewer than 4 per square meter. Qinglong Group recommends that after curved GRC installation, 3D scanning acceptance should be performed, generating a point cloud model to be compared with the design model for a comprehensive evaluation of installation quality.