GRC Component Embedded Anchor Bolt Installation: Six Core Requirements to Build a Solid Safety Foundation

Countersunk bolts are the “connecting bridge” between GRC components and the main building structure, and whether they are installed according to specifications directly determines the 20-year service safety of the components. Qinglong Group, with 28 years of deep expertise in the GRC field, has participated in GRC curtain wall projects of up to 300,000 square meters, such as the Shenzhen Pingshan High-Tech Zone Comprehensive Service Center, and knows the core points of embedded countersunk bolt installation well—their installation quality directly relates to the stability and durability of the building facade.

The installation of embedded countersunk bolts must strictly follow the Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC); negligence at any stage may lead to the risk of components loosening or falling off. Through years of project practice, Qinglong has kept the countersunk bolt installation pass rate stable at above 99.8%, establishing standardized operating procedures.

Substrate Compatibility: Meeting Both Countersunk Bolt Selection and Base Strength Requirements

Before installation, the bolt type must be selected according to the base material: chemical anchors are suitable for concrete bases, welded countersunk bolts for steel structures, and masonry bases require pre-embedded steel plates for reinforcement in advance. Qinglong requires the compressive strength of the base to be no lower than C30, and the effective anchoring depth of the anchor to be no less than 10 times the anchor diameter. In the Hainan International Convention and Exhibition Center project, connection stability was ensured through base strength testing and precise matching of countersunk bolts.

Precise Positioning: BIM Technology Controls Installation Accuracy

Countersunk bolt positioning requires 3D modeling with BIM technology, with errors controlled within ±2mm. In the installation of double-curved GRC components for the Guangxi New Media Center, Qinglong used laser scanning positioning to ensure countersunk bolts were evenly distributed, with spacing no greater than 600mm and an edge distance from the component edge of no less than 50mm, avoiding stress concentration. After positioning, the coordinates must be rechecked to ensure precise alignment with the component installation holes.

Hole Drilling and Cleaning: Avoiding Impurities That Affect Anchoring Performance

The drilling diameter must match the countersunk bolt specifications, with an error of no more than ±1mm. After drilling, dust and debris inside the hole must be removed with compressed air, then cleaned a second time with a brush, and finally the hole wall wiped with acetone. Qinglong strictly implements the “three-step cleaning” standard during construction to prevent impurities from causing weak bonding between the countersunk bolt and the hole wall, which would affect load-bearing capacity.

Installation and Fixing: Torque Control and Curing Maintenance

The installation of chemical anchors requires control of the adhesive mixing time and curing temperature; the curing time at room temperature must be no less than 24 hours, extended to 48 hours in low-temperature environments. When installing mechanical anchors, the torque applied by the torque wrench must comply with the product manual requirements, generally 8-12N·m. In the National Service Center project in Singapore, Qinglong ensured consistency in countersunk bolt installation through standardized torque control.

Anti-Corrosion Treatment: The Key to Extending Service Life

The exposed parts of countersunk bolts must be coated with two coats of anti-rust paint, welds additionally treated with anti-corrosion coating, and anti-corrosion gaskets installed at the connection between components and countersunk bolts. In coastal projects, Qinglong uses hot-dip galvanized countersunk bolts combined with special anti-corrosion coatings, effectively resisting chloride ion corrosion and extending the service life of countersunk bolts to more than 20 years.

The installation of embedded countersunk bolts is the foundation for the safe service of GRC components, requiring attention to multiple requirements including selection, positioning, drilling, fixing, and anti-corrosion. Drawing on 28 years of project experience, Qinglong has incorporated countersunk bolt installation into full-process quality control, with supervision throughout from design deepening to on-site construction. Only by following scientific installation standards can the “connecting bridge” of GRC components remain indestructible, safeguarding building safety.