Analysis of Anti-Rust Measures and Key Installation Points for Top-Burst Screws in GRC Component Installation

Prevention Before Problems: A Complete Guide to Anti-Rust Treatment for Expansion Anchor Screws in GRC Component Installation

In the installation of GRC (glass fiber reinforced concrete) architectural decoration components, expansion anchor screws serve as critical nodes connecting the structure to the components, and their anti-rust treatment directly affects the safety, durability, and aesthetics of the building facade. Drawing on 28 years of full-chain experience with UHPC/GRC/GRG/GRP materials, Qinglong Group provides an in-depth analysis of the corrosion mechanisms of expansion anchor screws and systematic anti-rust solutions, offering professional technical references for designers and contractors.

Dangers and Causes of Expansion Anchor Screw Corrosion in GRC Components

As the "invisible skeleton" of GRC components, expansion anchor screws are exposed long-term to rainwater, ultraviolet rays, and industrial pollutants, making them prone to electrochemical corrosion. A case from a commercial complex project showed that screws without anti-rust treatment developed rust-induced expansion just 6 months after installation, causing cracking at GRC panel joints and increasing repair costs by 30%. Through electron microscope analysis, Qinglong's technical team found that in the high salt-spray environment of coastal areas, screw corrosion rates are 2.3 times those of inland areas, with chloride ion penetration being the main cause.

Three-Tier Anti-Rust System: Full-Process Control from Materials to Construction

Qinglong's GRC installation specifications adopt a three-tier protection system of "material pretreatment - on-site protection - long-term maintenance." On the material side, Dacromet-coated (zinc-chromium coating) screws are selected, with salt spray testing exceeding 1,000 hours—an anti-rust capability 5 times greater than ordinary galvanized screws; before installation, special sealing treatment is applied to the threaded portions, using Qinglong's patented anti-rust adhesive (Patent No. ZL2023XXXXXX) to form an elastic protective film. During on-site construction, screw holes must undergo secondary cleaning and dust removal, and after screws are inserted, they are immediately sealed with polymer waterproof mortar to form a physical barrier.

Key Construction Control Points and Quality Acceptance Standards

In the practical installation of GRC components, four core aspects require strict control: drilling depth deviation must be kept within ±2mm to ensure the effective anchorage length of the screws; torque wrenches must be set to the rated torque (45-50N·m recommended for M12 screws) to avoid over-tightening that damages the coating; anti-rust sealing must be completed within 24 hours after installation, with temporary shielding measures taken on rainy or overcast days; during acceptance, coating thickness gauges are used to test the film thickness, ensuring it meets the standard of 80μm or above. The BIM model developed by Qinglong's detailed design team enables pre-layout of screw positions, reducing on-site drilling errors.

Full Life-Cycle Maintenance: From Project Handover to Ongoing Upkeep

As a national high-tech enterprise, Qinglong has established a comprehensive GRC project archive system, recording three-dimensional coordinates of expansion anchor screw positions. During the after-sales maintenance stage, visual inspections are recommended every 2 years, focusing on checking for rust penetration around the screws. For projects in coastal and high-humidity areas, Qinglong's specially formulated silane impregnation agent can be used for regular maintenance, extending the anti-rust cycle to more than 15 years. In accelerated aging tests at the Nanning production base, this maintenance plan reduced screw corrosion rates by 82%.

Anti-rust treatment of expansion anchor screws is the "last mile" of quality control in GRC engineering, requiring systematic coordination of material selection, construction techniques, and later-stage maintenance. Qinglong Group will continue to leverage its 28 years of professional experience and, with an attitude of "meticulousness and pursuit of excellence," provide designers and owners with full-chain GRC solutions from detailed design to after-sales maintenance, helping create architectural works that combine aesthetic value with structural safety. As a vice-chairman unit of the China GRC Association, Qinglong participated in formulating the Technical Standard for Architectural Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), which has become an important reference for anti-rust construction in the industry.