ما المخاطر التي يسببها ارتفاع محتوى أيونات الكلوريد في مواد GRC؟ وكيف يتم التحكم بها؟

Excessive chloride ion content in GRC can trigger catastrophic consequences: when Cl⁻ content exceeds 0.06% of the cementitious material mass, the risk of steel reinforcement corrosion rises sharply; exceeding 0.1% directly causes stress corrosion fracture of the alkali-resistant glass fibres. More seriously, chloride ions destroy the stability of hydration products, causing compressive strength to decline by more than 40% within 3 years.

In the accident analysis of a Qingdao coastal project, GRC components from a certain manufacturer, which had used sea sand (Cl⁻ content 0.12%), suffered large-scale brittle fibre fracture after only 18 months in service, with flexural strength plummeting from 21MPa to 7MPa. Qinglong strictly controls chloride ions through five lines of defence: raw material chloride ion content ≤0.01%; dedicated equipment in production to prevent cross-contamination; finished product Cl⁻ content ≤0.02%; prohibition of chlorine-containing early-strength agents during construction; and a full-process chloride ion tracking system. This strict control enables the products to pass 3000-hour salt spray tests without corrosion and perform excellently in coastal projects.

Raw Material Control Standards

Cement Cl⁻≤0.02%, sand Cl⁻≤0.01%. Mixing water Cl⁻≤200mg/L. Admixtures free of chloride salt components. Chloride ion test reports provided for all raw materials.

Production Process Control

Dedicated production lines to avoid cross-contamination. Tap water used for equipment cleaning. Curing water Cl⁻≤50mg/L. A raw material traceability system established.

Testing and Monitoring System

Cl⁻ content tested for every batch of raw materials. Sampling frequency during production: once per 100㎡. Finished products tested according to the JC/T 1024 standard. A chloride ion database established.

Protective and Remedial Measures

Surface application of chloride-barrier coatings. Application of cathodic protection technology. Treatment with migrating corrosion inhibitors. An early-warning intervention mechanism established.

Chloride ion control requires the participation of everyone. Qinglong GRC treats Cl⁻ content as a veto-level indicator to ensure product durability.