Wind load is the force exerted by the wind on a structure, such as a building, bridge, tower, or any other structure exposed to wind. Wind load is an important consideration in the design of structures, as it can cause significant damage or failure if not properly accounted for.
Different types of wind load with examples are:
- Static wind load: This is the pressure exerted by the wind on the structure when it is stationary. This is calculated based on the wind speed, direction, and the geometry of the structure.
- Dynamic wind load: This is the pressure exerted by the wind on the structure when it is in motion, such as due to gusts, vibrations, or wind turbulence. This is calculated based on the frequency, amplitude, and duration of the wind gusts, as well as the mass and stiffness of the structure.
- Wind shear: This is the variation in wind speed and direction at different heights above the ground. Wind shear can cause differential pressures on the structure, leading to structural instability and damage.
- Topographic wind effects: This is the wind flow pattern that is affected by the shape and size of the terrain surrounding the structure. Topographic effects can cause variations in wind speed and direction, leading to changes in the wind load on the structure.
To calculate wind load, various factors such as wind speed, direction, duration, and terrain must be considered. Building codes and standards provide guidelines for calculating wind load based on the type of structure and its location. The load calculations are typically based on the design wind speed, exposure category, and terrain category specified in the building codes. Engineers may also use wind tunnel tests and computer simulations to determine the wind load on the structure, and to assess the structural response and safety under different wind load scenarios.