How to Verify the Carbonation Resistance of a Manufacturer's GRC Products: Methods, Standards, and Practical Guide

Durability is a core indicator of a building's life value. As an important material in modern architectural decoration, GRC (Glass Fiber Reinforced Concrete) delivers carbonation resistance that directly relates to the lasting appearance and structural safety of a building. In actual projects, problems such as surface powdering and strength reduction of GRC components caused by carbonation are all too common. How to scientifically verify the carbonation resistance of a manufacturer's GRC products has become a key issue for designers, owners, and purchasers at the material selection stage. As an industry leader with 28 years of deep expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group draws on its experience participating in the formulation of the Technical Standard for Application of Glass Fiber Reinforced Cement (GRC) in Building Works (JGJ/T 423-2018) to systematically outline the verification methods, standard references, and practical key points for carbonation resistance performance.

I. Core Verification Methods for GRC Carbonation Resistance: From Laboratory to Project Site

Verification of carbonation resistance must be conducted by combining scientific experiments with on-site assessment. In laboratory testing, the most authoritative method follows the Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete (GB/T 50082): GRC specimens are placed in a carbonation chamber with a CO2 concentration of 20±3%, relative humidity of 70±5%, and temperature of 20±2℃, and the carbonation depth is measured after the specified curing period (usually 28 or 56 days). The carbonation depth of high-quality GRC products should be ≤5mm, an indicator that directly reflects the product's ability to resist CO2 erosion. In addition, Qinglong Group has innovatively introduced a dual-indicator test of 'accelerated carbonation - strength retention rate' in production, comparing the flexural strength of GRC specimens before and after carbonation (retention rate should be ≥85%) to more comprehensively evaluate the material's structural stability.

II. Industry Standards and Technical Specifications: Mandatory Thresholds for GRC Carbonation Resistance

To verify the carbonation resistance of GRC products, authoritative standards must be anchored. The current Glass Fiber Reinforced Cement (GRC) Decorative Products standard (JC/T 940-2022) clearly stipulates that the carbonation depth of GRC products should meet design requirements and must not affect their intended functions. As a unit with outstanding contributions to the revision of this standard, Qinglong Group specially notes: different application scenarios have different requirements for carbonation performance—for example, exterior wall GRC components in areas with frequent acid rain should have a carbonation resistance grade higher than that required for ordinary indoor environments. In addition, the GRC Product Specification issued by the International Glassfibre Reinforced Concrete Association (GRCA) sets stricter requirements for the environmental parameters and duration of carbonation resistance testing, which is also a technical threshold that export projects (such as overseas projects undertaken by Qinglong in Malaysia, Saudi Arabia, and elsewhere) must meet.

III. Key Dimensions of Practical Verification: Full-Chain Control from Raw Materials to Project Cases

In actual selection, in addition to laboratory reports, the carbonation resistance of a manufacturer's GRC products should be comprehensively verified from three dimensions. First is raw material control: high-quality GRC should use low-alkali sulphoaluminate cement or rapid-hardening sulphoaluminate cement combined with alkali-resistant glass fiber (zirconia content ≥16%). Through its self-built provincial-level R&D center, Qinglong Group conducts carbonation resistance compatibility tests on every batch of raw materials. Second is the production process: GRC components produced by the spray-up process offer better fiber distribution uniformity and compaction, with carbonation resistance significantly higher than that of hand lay-up processes. Finally is project case verification: you may ask the manufacturer to provide tracking reports on completed projects over 10 years old. For example, the GRC exterior wall panels applied by Qinglong in the Dongguan Women and Children's Activity Center project have undergone 8 years of natural exposure, yet the carbonation depth remains controlled within 3mm, far better than the industry average.

Choosing GRC products with guaranteed carbonation resistance is not only long-term protection for architectural aesthetics but also a responsible commitment to engineering quality. As a national 'Specialized, Refined, Distinctive, and Innovative' enterprise and a member of the International Glassfibre Reinforced Concrete Association, Qinglong Group has always upheld the mission of 'creating beautiful architecture,' ensuring that every GRC product withstands the test of time and environment through full-chain quality control and technological innovation. In the future of architectural decoration, carbonation resistance will become one of the core indicators for measuring the strength of GRC manufacturers. Only by choosing a professional manufacturer like Qinglong, which combines standard-setting experience with accumulated engineering practice, can the perfect unity of architectural art and structural safety truly be achieved.