Embedded Anchor Installation Requirements and Key Technical Points

In the field of architectural decoration, the installation quality of pre-embedded countersunk bolts directly affects the structural safety and service life of components made of new materials such as UHPC and GRC. As Qinglong Group with 28 years of deep industry experience, we fully understand the critical impact of this step on project success. Drawing on full-chain technical experience, this article systematically explains the installation standards and core technical points of pre-embedded countersunk bolts, providing a professional reference for designers and engineering teams.

I. Basic Positioning and Material Matching Principles for Pre-Embedded Countersunk Bolts

As the core load-bearing component connecting the building main structure and external cladding components, the selection of pre-embedded countersunk bolts must strictly match material characteristics. Take Qinglong GRC components as an example: since their self-weight is only 1/4 that of natural stone, countersunk bolt design must balance lightweight requirements with pull-out resistance, typically using hot-dip galvanized bolts of 8-12mm diameter combined with an epoxy resin anchoring system. For UHPC (ultra-high performance concrete) components, with compressive strength exceeding 150MPa, countersunk bolt spacing must be optimized through structural calculation to ensure uniform load transfer.

II. Pre-Construction Technical Preparation and Precision Control

Professional detailed design is the prerequisite for embedding quality. Qinglong Group uses BIM technology for 3D positioning, keeping countersunk bolt coordinate errors within ±3mm. Before construction, the substrate must be treated: concrete surface flatness deviation should be ≤5mm/2m, and loose layers must be chiseled away and leveled with Qinglong special repair mortar. For interior scenarios such as GRG ceilings, the impact of ambient temperature and humidity on the curing speed of the countersunk bolt anchoring agent must also be considered; the recommended construction ambient temperature is 5-35℃.

III. Key Technical Points During Installation

1. Drilling Process: Drill holes with diamond drill bits; the hole diameter should be 2-4mm larger than the bolt diameter, and the hole depth must meet anchoring length requirements (usually ≥10d, where d is the bolt diameter). After drilling, dust inside the hole must be cleaned out with a high-pressure air pump to ensure full bonding between the anchoring agent and the substrate.

2. Anchoring Construction: When using Qinglong custom rebar planting adhesive, inject the adhesive slowly starting from the bottom of the hole; after the adhesive reaches 2/3 of the hole depth, insert the bolt and rotate it 90° to ensure the adhesive evenly coats the bolt. For composite material components such as GRP, metal embedded plates must be added at the countersunk bolt locations to avoid local stress concentration.

3. Acceptance Criteria: After installation, pull-out resistance testing is required. The countersunk bolt pull-out resistance should be ≥5kN for GRC components and ≥8kN for UHPC components, with a 100% test pass rate. Meanwhile, 3D scanning should be used to recheck overall position deviation to ensure compliance with design requirements.

IV. Full Life-Cycle Quality Assurance System

Qinglong Group has established a full-process control mechanism from detailed design to after-sales maintenance. In the production stage, countersunk bolt embedded parts use automated welding processes to ensure weld strength meets standards; during construction, certified installation teams are deployed and strictly implement the "three-inspection system"; after delivery, a 5-year warranty service is provided with regular countersunk bolt fastening tests. This full-chain service capability reflects Qinglong's strength as a national high-tech enterprise and a participant in setting GRC industry standards.

Although pre-embedded countersunk bolts are concealed work, they are the "lifeline" of architectural decoration safety. Qinglong Group's 28 years of engineering practice show that only by implementing refined management throughout the entire process of design, production, and construction can the long-term safety and stability of UHPC/GRC/GRG/GRP components be ensured. Going forward, we will continue with a "meticulous and striving-for-excellence" attitude to provide professional and reliable technical support for more landmark projects.