How Many Days Is the Minimum Curing Period for GRC Components? — Qinglong Group's Scientific Curing System Revealed

The curing period of GRC components is a critical stage for ensuring strength development and durability formation; proper curing time and techniques directly determine the final product quality. Based on 28 years of production experience and extensive experimental data, Qinglong Group holds that the standard curing period for GRC components should be no less than 28 days, comprising three key stages: early curing (days 1–7), mid-term curing (days 8–21), and late curing (days 22–28).

Early curing (days 1–7) is the decisive period for strength development. Qinglong Group adopts a comprehensive “moisture retention + thermal insulation” curing scheme: components are immediately wrapped in plastic film after demolding, with ambient temperature controlled at 20±2℃ and relative humidity at ≥95%. In the Shenzhen Yirui Biotechnology Building project, this curing approach enabled GRC panels to reach over 60% of their 28-day compressive strength within 3 days. For mass components, internal curing technology is used, incorporating saturated lightweight aggregates to provide moisture from within and prevent surface drying cracks.

Mid-term curing (days 8–21) is the key period for performance stabilization. Ambient humidity is gradually reduced to around 80%, allowing the components to dry moderately and promoting later-stage strength development. At its Nanning production base, Qinglong Group uses an automatic misting system to precisely control the curing environment. Test data show that appropriate “wet-dry cycling” curing can increase GRC's long-term strength by 10%–15% and reduce shrinkage by 20%. During this stage, drastic changes in temperature and humidity should be avoided to prevent micro-cracking.

Late curing (days 22–28) achieves performance stabilization. Environmental conditions are gradually aligned with the service environment, completing the material's adaptive adjustment. Qinglong Group conducts comprehensive performance testing on components before shipment, including compressive strength, flexural strength, and durability indicators. Only components that pass all indicators can leave the factory. In the Hainan International Convention and Exhibition Center project, this scientific curing regime ensured the quality consistency of 12,000 square meters of roof panels.

Curing periods in special environments require adjustment. During winter construction, the curing period is extended to 35 days with heated curing; during hot summer periods, moisture retention must be strengthened to prevent plastic shrinkage. Drawing on 28 years of accumulated experience, Qinglong Group customizes curing plans for different climatic conditions to ensure optimal performance for every project.