What is the wind resistance capacity of high-mast lights?
The wind resistance of a high-mast light depends primarily on the structural design of the mast, the stability of the foundation, and the wind resistance (drag) of the light fixtures. According to the Chinese national standard GB 50135, "Code for Design of High-rise Structures," high-mast lights must be designed based on a "basic wind pressure" corresponding to a 50-year return period; design wind speeds vary by region. For instance, the basic wind pressure in most inland areas ranges from 0.35 to 0.5 kN/m² (corresponding to wind speeds of approximately 23–28 m/s), whereas in coastal areas prone to typhoons, it can reach 0.8 to 1.0 kN/m² (corresponding to wind speeds of approximately 36–40 m/s).
For critical high-mast lighting installations (such as those at airports or ports), the design wind speed may need to be increased to 45 m/s or higher. In terms of actual products, standard high-mast lights are typically rated for Beaufort scale 12 winds (32.7–36.9 m/s), while high-quality models can withstand scale 13 (37.0–41.4 m/s) or scale 14 (41.5–46.1 m/s). Beyond wind speed, factors such as gust coefficients and vortex-induced vibration must be considered. Slender high-mast lights can experience vortex-induced resonance at specific wind speeds, potentially leading to fatigue failure; therefore, the installation of vibration dampers or spoilers is necessary. In coastal regions frequently affected by typhoons, it is advisable to use masts with thicker walls and reinforcing ribs, lower the center of gravity of the light assembly, and utilize wind-resistant fixtures (designed for low wind drag).
During installation, the foundation must be poured in strict accordance with design specifications, and anchor bolts must have a strength grade of at least 8.8. Prior to the annual typhoon season, inspections should be conducted to check the mast's verticality, bolt tightness, and the presence of any abnormal vibrations. Older high-mast lights should undergo a re-evaluation of their wind resistance and be reinforced if necessary.
