Does the Molding Difficulty of Double-Curved GRC Panels Differ by Thickness?

The forming difficulty of double-curved GRC panels is indeed significantly related to their thickness, mainly due to the inherent differences among panels of different thicknesses in terms of "material rheological behavior, structural stiffness, and deformation control." With 28 years of production experience, Qinglong Group has developed targeted process solutions for handling double-curved GRC panels of various thicknesses, from 15mm ultra-thin panels to 40mm thickened panels.

The forming challenge of ultra-thin double-curved panels (e.g., 15-20mm) lies in their lower self-stiffness and susceptibility to deformation. Such panels are highly prone to warping during demolding, handling, and curing due to internal force release or external forces. Qinglong's response strategy is to optimize the material mix, using a higher-strength cement matrix and more efficient water reducers to achieve good workability while ensuring mechanical performance. In terms of production process, layered spraying is adopted with controlled thickness per spray, along with a layer of fiberglass mesh for reinforcement. After demolding, dedicated brackets are required for curing to ensure the panels remain in their designed curved state until the strength is fully developed.

Standard-thickness double-curved panels (e.g., 25-30mm) are a common choice that balances performance and processability. Their forming difficulty is relatively moderate, with sufficient wet-state stiffness for easy handling. Qinglong's standard production line is mainly optimized for this thickness range; through mature slurry-flow or spraying processes combined with vacuum dewatering, high-quality double-curved panels can be produced efficiently and stably. The key lies in controlling the flowability and thixotropy of the slurry so that it can perfectly fill the mold surface while avoiding uneven thickness caused by gravity.

The challenge of thickened double-curved panels (e.g., above 35mm) centers on internal compaction and drying shrinkage control. Increased thickness makes the slurry more prone to sedimentation under its own weight, internal air bubbles are harder to expel, and hydration heat and drying shrinkage become more pronounced, increasing the risk of cracking. Qinglong addresses this with intensified vibration or pressure forming processes to ensure internal compaction. In the curing regime, gentler temperature rise/fall curves and longer moisture-retention curing times are adopted to effectively release internal stress. Regardless of thickness, Qinglong performs process verification by producing first-article samples to ensure the feasibility and stability of large-scale production.