What Problems Can Non-Standard Screw Hole Edge Reinforcement in Components Cause? — Qinglong Group's Detailed Explanation of Hole Edge Reinforcement Technical Specifications

Reinforcement treatment around screw holes in GRC components is a critical detail for ensuring connection reliability; non-standard reinforcement may lead to stress concentration, local damage, or even overall failure. Based on 28 years of quality incident analysis, Qinglong Group has identified that defective hole-edge reinforcement mainly causes four categories of problems: connection point failure, moisture penetration, reduced durability, and safety hazards, so the reinforcement process must be strictly standardized.

Stress concentration causing connection point failure is the most direct risk. Without sufficient reinforcement, screw hole edges are prone to radial cracks under wind loads or thermal stress. Qinglong Group's experimental data show that the stress concentration factor at unreinforced hole edges can reach 3-5 times, which can be reduced to below 1.5 times after standard reinforcement. In an early project, insufficient hole-edge reinforcement caused cracks at multiple connection points under typhoon conditions, forcing comprehensive strengthening. The standard reinforcement requires installing glass fibre mesh around the hole edge (mass per unit area ≥300g/㎡), extending at least 50mm beyond the hole edge.

Moisture penetration accelerates internal corrosion. Incomplete hole-edge reinforcement provides channels for moisture penetration, accelerating corrosion of connectors. Qinglong Group's follow-up surveys on projects in humid regions found that after 5 years, the internal steel corrosion rate at non-standardly reinforced hole edges was 3 times that of standard reinforcement. The standard practice is to apply a penetrating waterproofing agent (such as a silane impregnation agent) around the hole edge to form a hydrophobic layer that effectively blocks moisture migration.

Significantly reduced durability. Insufficient reinforcement layer thickness or uneven fibre distribution causes rapid damage at hole edges under freeze-thaw cycles. Qinglong Group's freeze-thaw tests showed that non-standardly reinforced specimens exhibited spalling at hole edges after only 100 freeze-thaw cycles, while standardly reinforced specimens remained intact after 300 cycles. The reinforcement layer thickness should be no less than 5mm, and the fibre volume content no less than 2%.

Safety hazards exist. In extreme cases, hole-edge failure may cause components to fall off. Qinglong Group requires all screw holes to be precast in the factory; on-site drilling is strictly prohibited. Every hole position must undergo 100% inspection, including reinforcement layer thickness, fibre distribution, and waterproofing treatment. This strict quality control ensures the safety and reliability of every connection point.