How to Verify a Manufacturer's GRC Product Carbonation Resistance? Testing Systems and Qinglong Group's Durability Assurance

Verifying the carbonation resistance of GRC products requires scientific evaluation across three dimensions: "laboratory accelerated testing, on-site sampling inspection, and long-term tracking data." Based on 28 years of durability research, Qinglong Group has established a complete carbonation resistance verification system: the laboratory conducts rapid carbonation tests (CO₂ concentration 20%) in accordance with the Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete (GB/T 50082), and the 28-day carbonation depth of premium GRC should be ≤1mm; on-site, core drilling plus the phenolphthalein reagent method is used to measure actual carbonation depth; at the same time, projects completed more than 5 years ago are tracked and monitored. In the 10th anniversary follow-up of the Hainan International Convention and Exhibition Center project, our on-site core testing showed a carbonation depth of only 0.8mm, with an estimated 100-year carbonation depth of less than 10mm, far below the thickness of the protective cover. Carbonation resistance is a key indicator of GRC longevity and must be scientifically verified.

Laboratory accelerated testing is a rapid evaluation method

Under standard conditions (temperature 20±2℃, humidity 70±5%, CO₂ concentration 20%), the 28-day carbonation depth is tested. With an optimized mix design (incorporating 25% silica fume), Qinglong GRC achieves a carbonation depth controlled at 0.5-0.8mm, equivalent to a carbonation depth of less than 5mm over 50 years in natural environments. We sample and test production line products every quarter, with the data entered into the quality management system.

On-site sampling is the most authentic performance verification

At key time points such as 3, 5, and 10 years after completion, 50mm-diameter core samples are drilled on-site, sprayed with 1% phenolphthalein alcohol reagent, and the depth of the color-change interface is measured. In the 8th anniversary inspection of the Wuhan Hanxiu Theater, the maximum carbonation depth among 20 sampling points was 1.2mm, with an average of 0.9mm, highly consistent with laboratory data.

Long-term data accumulation underpins credibility

Qinglong Group has established a project database containing carbonation data from more than 100 projects completed over 5 years ago. The data shows that in general atmospheric environments, the annual carbonation depth growth of our GRC is approximately 0.1mm, and in coastal high-humidity environments 0.15mm, fully meeting the 50-year design life requirement.

Comprehensive analysis of influencing factors drives performance improvement

The water-binder ratio (controlled at 0.32-0.38), silica fume content (≥20%), and curing regime (steam curing) are the key factors affecting carbonation resistance. Through optimized mix proportions and processes, our products achieve industry-leading carbonation resistance.

Verifying carbonation resistance requires combining theory with practice. Qinglong Group speaks with data and facts, providing customers with products that stand the test of time.