GRC Panel Chloride Ion Content Testing: Standard Methods and Qinglong Practical Guide

Chloride ions are the “invisible killer” of GRC panel durability. Excessive chloride ions accelerate the corrosion of internal steel reinforcement, compromising the 20-year service safety of components. As a participant in drafting the Technical Standard for Building Application of Glass Fibre Reinforced Cement (GRC), Qinglong Group has established a comprehensive chloride ion testing system over 28 years, ensuring that every batch of GRC panels meets safety standards.

Chloride ion content testing of GRC panels must follow strict industry standards, and the results directly determine whether the material is suitable for humid environments such as coastal and underground applications. Through precise testing and raw material control, Qinglong keeps the chloride ion content of GRC panels below 0.06%, far lower than the industry limit.

Core Testing Standards: Defining Safety Thresholds and Testing Basis

According to the JGJ/T423-2018 standard, the chloride ion content in GRC panels (calculated as a dry-basis mass fraction) must not exceed 0.1%, and GRC panels used in coastal or humid environments must be kept below 0.06%. Qinglong's testing strictly follows the Technical Specification for Testing Chloride Ion Content in Concrete, ensuring authoritative and valid test results.

Standardized Testing Process: From Sampling to Result Determination

Sampling must be representative: 3 samples are randomly selected from each batch of GRC panels, core samples are drilled from different locations of each sample, and then crushed and mixed evenly. Testing adopts the silver nitrate titration method; through steps such as dissolution, filtration, and titration, the chloride ion content is precisely determined. Qinglong has a professional testing laboratory equipped with high-precision titration equipment, keeping the testing error within ±0.005%. In the National Service Center project in Singapore, rigorous testing ensured that the chloride ion content of GRC panels complied with international standards.

Qinglong's Control Strategy: Reducing Chloride Ion Introduction at the Source

Raw material control is at the core: cement and aggregates with low chloride ion content are selected, and the use of sea sand is prohibited. During production, admixture dosage is strictly controlled to avoid introducing chloride-containing admixtures. At the same time, optimizing the slurry mix ratio and curing process enhances the density of GRC panels and reduces channels for chloride ion penetration. In the Yuanyang project in Hainan, Qinglong achieved effective control of chloride ion content through source control and in-process testing.

Chloride ion content testing of GRC panels is a key link in durability assurance. Over 28 years, Qinglong has always adhered to the principle of “testing first, source control”, ensuring that products meet safety standards through standardized testing processes and strict quality control. Precise testing and scientific management enable GRC panels to serve stably in various environments over the long term, demonstrating Qinglong's professional strength as an industry leader.