GRC Core Component Materials Explained: Key Technical Requirements and Selection Criteria for Alkali-Resistant Glass Fiber

The quality of materials determines the vitality of a building. GRC (Glass Fiber Reinforced Concrete), as a star material in the high-end architectural decoration field, owes its performance advantages to scientifically proportioned core components and stringent material selection standards. Qinglong, a national high-tech enterprise with 28 years of full-chain GRC experience, participated in formulating the Technical Standard for Architectural Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), and deeply understands the decisive role of core materials in the stability of GRC products.

The core material system of GRC exhibits a precise synergistic effect, mainly including cementitious materials, aggregates, reinforcement materials, mixing water, and functional admixtures. The cementitious materials are mainly low-alkalinity sulphoaluminate cement or ordinary Portland cement. In landmark projects such as the Wuhan Han Show Theatre, Qinglong selected high-grade low-alkali cement as the matrix, laying the foundation for GRC durability; aggregates give priority to clean inorganic aggregates such as quartz sand, with particle gradation meeting the requirements for construction fluidity and strength; the reinforcement material, namely alkali-resistant glass fiber, is the core for enhancing the flexural and tensile properties of GRC; mixing water must be clean and free of impurities to prevent harmful substances from affecting material stability; admixtures are precisely proportioned according to project requirements to optimize construction performance and end-use effects.

As the “skeleton” of GRC, the quality of alkali-resistant glass fiber directly determines product service life. Following high industry standards, Qinglong imposes three core requirements on alkali-resistant glass fiber: First, alkali resistance must meet standards—using an alkali-resistant glass composition with a zirconium content of ≥16% and a strength retention rate after alkali solution immersion of no less than 75%, ensuring long-term stability in the alkaline cement environment; Second, excellent physical properties—single filament diameter controlled at 13-18μm, with length adapted to the mixing process, usually 6-12mm, ensuring uniform dispersion of fibers in the concrete matrix; Third, strong interfacial bonding—surface treatment technology enhances the bonding effect with the cement slurry, enabling smooth stress transfer and fully exerting the reinforcement effect. In the 120,000-square-meter GRC roof project of the Hainan International Convention and Exhibition Center, the alkali-resistant glass fiber selected by Qinglong enabled thin-walled GRC components to achieve a dual breakthrough in impact resistance and crack resistance.

The creation of high-quality GRC is inseparable from the utmost control of every core material. Leveraging the technical strength of its provincial-level R&D center, Qinglong has established a full-process quality control system covering material procurement, testing, and proportion optimization. Its GRC products, in Luban Award projects such as the Shenzhen Pingshan High-tech Zone Comprehensive Service Center, have fulfilled the promise of over 20 years of non-declining strength through scientific material combinations. For designers and owners, selecting standard-compliant core materials and professional suppliers is the key to ensuring the decorative effect and durability of GRC architectural decoration.