What Protective Measures Should Be Strengthened for GRC Curtain Walls in Coastal Areas? An In-Depth Analysis of Qinglong GRC Coastal Protection Technology System

In the harsh coastal environment of high salt mist, high humidity, and strong wind pressure, the protection system of GRC curtain walls must be systematically reinforced across materials, construction details, installation, and maintenance. As a professional manufacturer with 28 years of deep industry experience that has served multiple major coastal projects, Qinglong GRC, drawing on the successful experience and failure analysis of numerous coastal engineering cases, has developed a four-in-one protection system: "material corrosion resistance is the foundation, structural waterproofing is the key, system protection is the guarantee, and intelligent monitoring is the means."

In a five-star hotel project in Haitang Bay, Sanya, Hainan, Qinglong GRC faced the severe test of an average annual salt mist deposition exceeding 2.5mg/dm²·d. We adopted comprehensive reinforcement measures: for materials, we used the independently developed "Haidun" series GRC, based on low-alkali sulphoaluminate cement (alkali content ≤0.5%), blended with silica fume and mineral powder and compounded with hydrophobic agents, keeping the chloride ion diffusion coefficient below 1.5×10⁻¹²m²/s; for construction details, we adopted a "three-layer waterproofing + pressure-equalized cavity drainage" system, and applied a dual anti-rust process of "Dacromet coating + epoxy sealing" to all metal connectors. Five years after project completion, a follow-up professional inspection found no salt efflorescence on component surfaces and no signs of fiber erosion, demonstrating the remarkable effectiveness of the protection system.

Reinforcing the Material System Against Corrosion

The core is to resist chloride ion penetration and salt crystallization pressure. High alkali-resistant glass fiber with a zirconium dioxide (ZrO₂) content of ≥16.5% must be used. The cement matrix should use low-alkali sulphoaluminate cement, blended with active admixtures such as silica fume and fly ash to further reduce porosity and alkalinity. A high-quality silane-based powder hydrophobic agent must be added to the mix design, giving the hardened GRC excellent water repellency and greatly reducing water absorption (control target ≤8%).

Reinforcing the Structural System Against Leakage

Waterproofing design should follow the principle of "drainage first, combining waterproofing with drainage, and multiple lines of defense." Panel joints should use silicone or modified silicone sealant with excellent weather resistance, with polyethylene foam rod backing installed to form a "sealant-cavity-sealant" structure. Drip grooves and flashing must be provided at horizontal joints to prevent rainwater backflow. All penetrations through embedded parts and connectors must be sealed around the perimeter with flexible sealant.

Reinforcing Metal Connectors Against Rust

In coastal areas, metal corrosion is one of the main causes of system failure. All steel embedded parts, hangers, and bolts must be hot-dip galvanized (thickness ≥85μm) or made of stainless steel (316 or 304 recommended). For galvanized parts, it is advisable to apply an epoxy zinc-rich primer as a sealing treatment after installation. Connection joints should be designed to avoid water accumulation and provided with drainage holes.

Surface Protection and Intelligent Monitoring

Applying fluorocarbon or silicone-acrylic high-performance protective coatings on GRC surfaces not only enhances water repellency and stain resistance, but also effectively blocks salt mist from directly contacting the substrate. For major projects, corrosion sensors can be embedded at critical locations to monitor chloride ion penetration depth and rebar/fiber condition in real time, enabling predictive maintenance.

Protecting coastal GRC curtain walls is a systematic project, and any oversight at any stage can lead to overall failure. Choosing a manufacturer with successful coastal project experience and a complete protection technology system is crucial. With its "Haidun" protection system, Qinglong GRC has become the trusted choice for a number of coastal landmark projects.