September 25, 2015 by Cory Hays

Why You Need To Know The Importance of Wind Load

Nature has various forms of powerful forces. Earthquakes, volcanic eruptions and floods are some of them to name a few. Nature’s fury can also be very well seen or experienced during hurricanes, storms and tornadoes! The force of nature that is common cause of destruction in all of these three phenomena are WINDS! Fast, furious, vague and strong wind energies! These forces cause mass destruction every year on our planet, resulting in the loss of lives and properties.

To prevent or reduce these losses during such wind calamities, a concept of Physics called WIND LOAD is widely used in the modern day construction field. This concept is extensively used by scientists, architects, and engineers during the designing and construction phases of tall buildings or skyscrapers which need to face speedy winds or harsh weather conditions. Hence the Wind Load is calculated for the safety of life and property.

What Is Wind Load?

Before we go deeper into the concept of Wind Load, you need to understand what exactly it is. In simple language, it is the force, pressure or impact exerted by the wind on a structure. Higher this wind impact on a structure, higher the Wind Load whereas lower the wind impact on a structure, lower the Wind Load. It is the load which a structure carries during various wind velocities.

Why To Calculate Wind Load?

wind_loads_calculationsAs already discussed, calculating Wind Load is important to prevent damages to a structure. With its application, wind patterns and wind impacts are studied, and a wind resistant environment is created wherein the chances of danger to life and property due to winds are minimized.Although one note worthy point here is that Wind Load depends on the dimensions of the structure as well. The shape, size, area, design, material, etc of the structure are the factors which have their impact on the Wind Load. For example, the Wind Load on a small house will be different than the Wind Load on a tower, at the same place under same wind speed. You can calculate these factors with a wind load calculator or you can use the formula we discuss next.

How To Calculate Wind Load?

Wind Load can be calculated with the below mentioned formula –
F = A x P x Cd
where, F = Wind Load, A = Area of the surface, P = Wind Pressure, Cd = Drag Coefficient

You may use basic formula to calculate Area depending on their shapes and insert it in the above formula for calculating Wind Load.

The unit of Wind Pressure is Psf meaning “pounds per square foot”. Wind Pressure is calculated with below formula –
0.00256 x V^2
where, V = speed of the wind in miles per hour

Now, regarding the calculation for Drag Coefficient, it is the value depending on the shapes of the object or structure on which the wind will have an effect. Different shapes have different resistance powers to winds and these values are nothing but the Drag Coefficients of those particular shapes. The Drag Coefficients of various shapes are already determined by the engineers! These values can be directly inserted in the formula for calculating Wind Load.

This was the basic formula to determine the Wind Load on a structure, but there are other factors or variables as well which may to be taken into account while calculating the Wind Load. These factors are wind speeds at different heights, wind directions, temperature, etc.

With this, you would understand how important the concept of Wind Load is in modern day constructions!So the next time you look at a huge building or a tall bridge, just thank the engineers in your mind and wonder what Wind Load that structure is carrying!