Research on Alkalinity Issues and Response Strategies When Applying Sulphoaluminate Cement in GRC

In the field of modern architectural decoration, GRC (Glass Fiber Reinforced Concrete) has become the preferred material for high-end projects such as grand theaters, commercial complexes, and landmark buildings, thanks to its lightweight, high-strength, and flexible molding characteristics. However, the scientific application of materials directly determines project quality—as an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP, Qinglong Group has found through in-depth design and engineering practice that the alkalinity issue of sulfoaluminate cement in GRC products has become a key technical pain point affecting component durability and safety.

The Alkalinity Challenge of Sulfoaluminate Cement: From Material Properties to Engineering Risks

Sulfoaluminate cement is widely used in GRC component production due to its rapid hardening, early strength development, and excellent impermeability. However, its hydration process releases a large amount of hydroxide ions, keeping the system's pH value in a strongly alkaline environment above 12.5 for an extended period. This high-alkalinity condition is particularly corrosive to glass fibers: under strong alkali, the silicon-oxygen bonds in ordinary E-glass fibers undergo hydrolysis, with strength loss reaching over 30% within 28 days, directly affecting the flexural performance and service life of GRC components. A landmark project once failed to control alkalinity, resulting in surface powdering and fiber exposure of exterior wall GRC cladding panels after 3 years, with later maintenance costs reaching 40% of the initial construction cost.

Multi-Dimensional Response Strategies: Solutions from Qinglong's 28 Years of Technical Expertise

As an enterprise that participated in formulating the "Technical Standard for Building Applications of Glass Fiber Reinforced Cement (GRC)" (JGJ/T423-2018), Qinglong Group has built a systematic solution through a three-dimensional framework of material optimization, process innovation, and quality control. At the material level, the golden ratio of low-alkalinity sulfoaluminate cement (alkali content ≤0.6%) and alkali-resistant glass fiber (ZrO₂ content ≥16%) is adopted; verified by accelerated aging tests, the flexural strength retention rate of components can reach over 85%. At the process level, Qinglong's patented "gradient alkalinity control technology" is introduced, which through the synergistic reaction of composite mineral admixtures reduces the alkalinity gradient of hardened cement by 30%, while vacuum extrusion molding is adopted to improve density and reduce alkali ion migration channels.

For different application scenarios, Qinglong provides customized solutions: in humid environments such as municipal gardens, an "alkalinity buffer layer" design is adopted, using interface treatment agents to block alkali penetration paths; for special-shaped components in high-end commercial buildings, BIM technology is combined to simulate alkalinity distribution, optimizing reinforcement and anchoring nodes in advance. In the Nanjing East Road Century Plaza renovation project, the light-transmitting UHPC-GRC composite panels produced by Qinglong using this technical system not only achieved structural safety across a 3.6-meter span, but also ensured the stability of the decorative effect for more than 15 years through alkalinity control.

Full-Chain Quality Control: A Quality Management Closed Loop from Laboratory to Construction Site

Relying on the R&D strength of a national high-tech enterprise, Qinglong has established an industry-leading alkalinity monitoring system: X-ray fluorescence spectrometers are used to test cement alkali content when raw materials enter the site, an online pH monitoring system regulates slurry alkalinity in real time during production, and 72-hour leachate alkalinity testing is conducted before finished products leave the factory. At the construction and installation stage, 3D laser scanning positioning technology is applied to ensure the alkali resistance of sealant at component joints and the durability of the overall structure. This full-process control model of "laboratory R&D – factory prefabrication – on-site installation" has enabled projects undertaken by Qinglong, such as the Dongguan Women and Children's Activity Center, to maintain zero alkali-corrosion-related complaints 5 years after delivery.

In the field of new architectural decoration materials, the control of technical details determines the final quality of a project. Qinglong Group, with 28 years of professional accumulation, has integrated alkalinity control technology into the whole life cycle management of GRC components, not only providing designers with broader creative space, but also reducing long-term maintenance costs for owners. In the future, with the implementation of standards such as the "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)", Qinglong will continue to promote the deep integration of materials science and engineering practice, contributing technical strength to the creation of aesthetically beautiful architecture.