What Protection Should Be Strengthened for GRC Exterior Walls in Acid Rain Areas?

Acid rain environments pose a severe challenge to the durability of GRC exterior walls, requiring targeted protective measures. From projects in acid rain regions, Qinglong Group has developed a three-in-one protection system combining material modification, surface treatment, and regular maintenance.

Material modification improves acid resistance. Low-alkalinity cement (alkali content ≤0.6%) is used, with slag powder (20%-30%) and silica fume (10%-15%) added to reduce Ca(OH)₂ content. In a Chongqing project, Qinglong Group optimized the mix ratio to improve the acid resistance of GRC threefold, achieving a mass loss rate below 0.5g/m²·year.

Surface treatment forms a protective layer. Fluorocarbon coatings offer the best acid resistance, reaching AA-grade acid resistance. Qinglong Group adopts a double-layer coating system: an epoxy primer provides adhesion, while a fluorocarbon topcoat delivers weather and corrosion resistance. The total dry film thickness of the coating is ≥80μm, effectively blocking acid rain erosion. The coating is inspected regularly for integrity, and any damage is repaired promptly.

Drainage design reduces acid rain retention. Adequate drainage slopes (≥5%) are set to avoid water accumulation. Acid-resistant sealant is applied at joints and inspected and replaced regularly. Through systematic protection, GRC exterior walls can maintain stable long-term performance in acid rain environments.