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

In the installation of GRC components, expansion anchor bolts serve as key nodes connecting components to the main structure, and their rust-proofing treatment directly affects the safety and durability of architectural decoration. As an industry leader with 28 years of experience in detailed design, manufacturing, and construction of UHPC/GRC/GRG/GRP materials, Qinglong Group leverages its full-chain technical advantages to form a systematic rust-proofing solution for expansion anchor bolts, from material selection and process control to quality acceptance, providing professional construction technical support for designers and owners.

I. Hazards and Causes of Expansion Anchor Bolt Corrosion in GRC Components

GRC components (Glass Fiber Reinforced Concrete), with their lightweight, high-strength and flexible shaping characteristics, are widely used in exterior wall decoration of high-end projects such as grand theaters, commercial complexes, and landmark buildings. As core parts of concealed works, expansion anchor bolts are exposed long-term to complex outdoor environments involving moisture, ultraviolet radiation, and temperature variations. If rust-proofing measures are inadequate, the bolts are prone to oxidation, corrosion and strength degradation, and may even cause components to loosen and fall off, creating safety hazards. Industry research data show that about 30% of post-installation maintenance problems of GRC components stem from corrosion failure of the anchoring system, so rust-proofing treatment is a top priority in construction. For more industry information: +WeChat qlfsbl123

II. Core Technical Measures for Rust-Proofing Treatment of Expansion Anchor Bolts

#1. Material Selection: Improving Rust-Proof Performance at the Source

For its projects, Qinglong prioritizes 316 stainless steel expansion anchor bolts complying with the "Technical Requirements for Passivation Treatment of Corrosion-Resistant Stainless Steel Fasteners". Their chromium-nickel-molybdenum alloy composition forms a stable passivation film on the surface, delivering salt spray resistance of over 1,000 hours, far exceeding ordinary carbon steel screws (about 200 hours). For projects in high-humidity or coastal areas, a combined hot-dip galvanizing + epoxy coating treatment process is also applied, and this dual protection ensures bolt durability in extreme environments. Meanwhile, the matching expansion sleeves are made of nylon 66 to avoid the risk of galvanic corrosion between metals.

#2. Construction Process: Standardized Workflow for Detail Quality Control

Before installing GRC components, the Qinglong construction team thoroughly cleans the base structure, removing floating dust, oil stains and rust to ensure the bolt installation surfaces are dry and clean. Drilling depth and diameter strictly follow the design parameters, with hole diameter deviation controlled within ±0.5mm to avoid poor sealing caused by excessive gaps at the hole walls. After the bolts are tightened, a specialized waterproof and rust-proof paste (mainly a zinc-rich coating with inorganic zinc content ≥95%) is applied to seal the bolt heads and surrounding gaps, then covered with repair mortar matched to the GRC component color, forming a physical isolation barrier. Water exposure should be avoided within 48 hours after construction to ensure the rust-proof coating cures fully.

III. Key Points and Quality Control of GRC Component Installation

#1. Positioning and Setting Out: Precision Determines Overall Stability

Relying on BIM technology and 3D laser scanning, Qinglong's detailed design team carries out component layout and bolt positioning in advance, ensuring that the load-bearing points of each expansion anchor bolt meet structural mechanics requirements. On site, a total station is used to re-verify the layout, with planar position deviation ≤3mm and elevation deviation ≤2mm, preventing uneven bolt loading caused by inaccurate positioning. For double-curved and irregular GRC components, pre-embedded inserts are combined with adjustable connectors to enable fine adjustment during installation, keeping the bolts in the optimal loading state.

#2. Acceptance Criteria: Full-Process Traceability of Quality Responsibility

Qinglong has established a strict acceptance system for expansion anchor bolt installation: before construction, bolt material certificates and third-party test reports are verified; during construction, torque wrenches are used to control the tightening torque (usually 1.2 times the design value), and the number and installation data of each bolt are recorded; after construction, pull-out tests are performed, requiring the pull-out resistance of a single bolt to be no less than 5kN and the pass rate to reach 100%. In addition, RFID chip technology is used for information-based management of key nodes, providing traceable evidence for later maintenance and fulfilling the quality commitment of "meticulous in every detail, striving for excellence". For more industry information: +WeChat qlfsbl123

As a national high-tech enterprise and a participant in formulating GRC industry standards, Qinglong Group always puts technological innovation and engineering quality first. Through refined control of the rust-proofing treatment of expansion anchor bolts, combined with its full-chain service capabilities for UHPC/GRC/GRG/GRP materials, it provides customers with one-stop solutions from detailed design to after-sales maintenance, helping to create safe, durable, beautiful and practical architectural decoration works. Going forward, Qinglong will continue to cultivate the field of new architectural decoration materials, drive industry technological progress with professional strength, and fulfill its corporate mission of "creating beautiful architecture".