Research on Steam Curing Parameter Setting Methods and Optimization Strategies for Precast UHPC Components

Steam Curing Process: The Core Key to Unlocking UHPC Component Performance

Amid the wave of innovation in building materials, ultra-high performance concrete (UHPC) is becoming the preferred material for landmark buildings, high-end curtain walls and other fields thanks to its outstanding mechanical properties and durability. As an industry specialist with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group deeply understands the decisive impact of the steam curing process on component quality. Scientifically setting curing parameters can not only raise the compressive strength of UHPC above 150MPa, but also optimize its microstructure, ensuring long-term stable performance in complex building environments.

I. The Golden Triangle of UHPC Steam Curing Parameters: Temperature, Humidity and Time

Steam curing is a key step in activating the potential of UHPC materials, requiring precise control of three core parameters. The heating stage should be controlled at a rate ≤20℃/h to avoid cracking caused by internal-external temperature differences; the constant temperature stage is best maintained at 80-90℃ for 6-8 hours to promote full cement hydration; the cooling stage rate must be ≤15℃/h to ensure uniform release of internal stress in components. Through an intelligent temperature control system, the Qinglong production base keeps curing environment humidity stable above 90%, combined with staged temperature control curves, raising the 28-day strength compliance rate of UHPC components to 99.6%.

II. Curing Plan Optimization Strategies Based on Component Characteristics

For different types of UHPC components, curing strategies need to be designed differentially. For thin-walled decorative components (such as curtain wall panels), gradient heating is adopted to reduce shrinkage stress; for large load-bearing components, the constant temperature time is extended to 10 hours to enhance the density of the interfacial transition zone. Comparative experiments by the Qinglong R&D Center found that under 85℃ constant temperature conditions, the flexural strength of UHPC components with steel fibers increased by 23% compared with conventional curing. In addition, combined with BIM technology to simulate the temperature field distribution of components, precise pre-control of curing parameters can be achieved; this technology has been successfully applied to the translucent concrete project at Nanjing East Road Century Plaza.

III. Curing Quality Assurance System from a Full-Chain Perspective

The birth of high-quality UHPC components depends on full-process control from raw materials to curing. Qinglong Group has established a trinity quality standard of "material-forming-curing", using active admixtures such as silica fume and ultrafine mineral powder to optimize matrix formulas, ensuring component density through high-frequency vibration, and combining precise control of steam curing to form a complete quality loop. As a participating unit in formulating the industry standard "General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components", Qinglong has transformed 28 years of engineering experience into standardized curing plans and can provide customized process support according to project needs, such as the curing regulations for high-temperature and high-humidity environments developed for overseas projects in Malaysia.

IV. Curing Process Innovation: Expanding the Application Boundaries of UHPC

With the innovative application of UHPC in special-shaped components, translucent curtain walls and other fields, traditional curing processes are constantly being upgraded. The pulsed steam curing technology developed by Qinglong promotes the generation of C-S-H gel through periodic temperature fluctuations, increasing the early strength of components by 40% and effectively shortening production cycles. In the Dongguan Women and Children's Activity Center project, this technology successfully solved the curing challenges of hyperbolic GRC-UHPC composite components, achieving a perfect unity of complex shapes and structural performance. In the future, combined with new technologies such as microwave curing and carbon fiber heating curing, the production efficiency and performance of UHPC components will achieve greater breakthroughs.

As a leader in the field of new architectural decoration materials, Qinglong Group has always taken "creating beautiful buildings" as its mission, transforming technical expertise in core process steps such as steam curing into professional solutions serving designers and owners. From parameter setting to process optimization, from laboratory research to engineering practice, every step embodies a deep understanding of the essence of materials. Choosing Qinglong means not only choosing high-quality UHPC/GRC/GRG/GRP products, but also choosing a reliable partner backed by a complete technical system, jointly building a harmonious unity of architectural aesthetics and engineering performance.