Analysis of Key Technical Points and Implementation Strategies for Steam Curing of GRC Components in Low-Temperature Environments

Analysis of Key Technical Points and Implementation Strategies for Steam Curing of GRC Components in Low-Temperature Environments

In the field of architectural decoration, GRC (glass fiber reinforced concrete) has become the ideal choice for high-end projects such as grand theaters, commercial complexes, and landmark buildings, thanks to its lightweight, high-strength, and richly formable characteristics. However, producing GRC components in low-temperature environments poses curing challenges that directly affect product strength and durability. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP, Qinglong Group leverages the R&D capabilities of a national-level high-tech enterprise to provide an in-depth analysis of the key technologies of low-temperature steam curing, offering professional solutions for the industry.

I. Core Challenges of Low-Temperature Environments for GRC Component Curing

Low-temperature environments (typically referring to ambient temperatures below 5℃) significantly retard cement hydration reactions, causing GRC components to gain strength slowly and become prone to quality problems such as cracking. Traditional natural curing methods often fail to meet construction schedules in winter or cold regions, whereas steam curing, through artificial control of temperature and humidity, can effectively address this pain point. Practice at Qinglong Group's production base in Nanning, Guangxi, shows that a scientific steam curing process can increase the 28-day strength of GRC components in low-temperature environments by more than 30%, with surface flatness reaching industry-leading standards.

II. Key Technical Points of Steam Curing for GRC Components

1. Gradient Temperature-Rise Control Technology: A three-stage heating method is adopted. In the initial stage (0–2 hours), the temperature is raised to 40℃ at a rate of 5℃/hour to avoid stress concentration inside components caused by sudden temperature increases; in the constant-temperature stage (2–6 hours), a temperature of 45–50℃ is maintained to ensure full cement hydration; in the cooling stage (6–8 hours), the temperature is slowly lowered to room temperature at 3℃/hour to prevent surface shrinkage cracking. Qinglong's self-developed intelligent temperature control system achieves precision control of ±1℃, outperforming the industry average.

2. Coordinated Adjustment of Humidity and Air Velocity: The relative humidity inside the curing chamber must be maintained above 90%, while air circulation is achieved through variable-frequency fans to prevent localized condensation accumulation. For the dry climate of northern regions, Qinglong has innovatively adopted atomized humidification devices, raising humidity uniformity to 95% and effectively reducing surface sanding on components.

3. Optimization of Component Placement and Steam Distribution: Multi-tier racks are used to ensure uniform steam flow between components, with spacing controlled at 15–20 cm. For special-shaped GRC components (such as double-curved exterior wall panels), custom molds reserve steam channels to solve the problem of inadequate local curing. This technology has been successfully applied in the renovation project of Century Plaza on Nanjing East Road, ensuring the forming quality of light-transmitting concrete components.

III. Qinglong Group's Full-Chain Implementation Strategy

As a participating drafting unit of the Technical Standard for Architectural Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), Qinglong has incorporated steam curing into the whole-process management of GRC production:

1. Pretreatment Stage: Raw materials are preheated, raising the temperature of cement and sand to above 15℃ to reduce the impact of low temperatures on initial hydration;

2. Curing Monitoring: Curing data is integrated through BIM technology, with temperature and humidity curves uploaded in real time to a cloud management platform to enable quality traceability;

3. Post-Curing Assurance: After steam curing is completed, film covering is used to maintain moisture for 72 hours, combined with Qinglong's patented curing agent, to further enhance component durability.

IV. Industry Value and Application Cases

Qinglong Group's low-temperature steam curing technology has served a number of key domestic projects, such as the GRC curtain wall project of a cultural center in a northern city, achieving stable daily production of 1,200 ㎡ of components at -10℃ and shortening the construction period by 40% compared with traditional processes. This technology is applicable not only to GRC, but also provides valuable reference for the low-temperature production of UHPC, GRG, and other materials, reflecting Qinglong's technical expertise as a "full-chain service provider of new decorative building materials."

Steam curing of GRC in low-temperature environments is a systematic combination of material properties, process control, and engineering management. Founded on 28 years of industry experience, Qinglong Group continues to drive breakthroughs in GRC applications in cold regions through technological innovation and standard setting, providing designers and owners with solutions that combine aesthetic effect and engineering reliability, and fulfilling its corporate mission of "Creating Beautiful Architecture."