The document discusses calculating wind load on buildings. Wind applies horizontal force or load to buildings through pressure. Internal pressure can also develop and act as negative pressure. Wind load calculation considers factors like wind speed, projected area of the building, and drag coefficient to determine the force in pounds or newtons applied. The generic formula is force equals area times pressure times drag coefficient. An example calculation is shown to find the 1.25 pound wind load on a short cylinder building with given dimensions in 70 feet/second winds.

2. Calculate wind load on any building
Mahreen Zamir Abro
14ce-16

3. Wind load :
Wind represents masses of air moving mainly horizontally
(parallel to the ground).
The main effect of wind is a horizontal loading of buildings
(especially high-rise).

4. When the wind enters the building from the windward side and
leeward side is relative closed, internal pressure is developed
that acts like negative pressure Similarly, when high speed wind
passes by a building, it produces a vacuum on the leeward side,
this vacuum results in internal suction producing negative
pressure from the structure Keeping the movements in the
upper levels of the building to acceptable human tolerances is
the goal of the structural engineer

9. Types ofWind Load Forces on Buildings:
Shear Load
Lateral Load
Uplift Load

11. Wind Load Calculation :
In order for a structure to be sound and secure, the
foundation, roof, and walls must be strong and wind
resistant.

12. Calculations :
The generic formula for wind load is Fw = A x P x Cd .
The simple formula for wind pressure P in imperial units
(pounds per square foot) is P=0.00256V^{2} and the pressure
in SI units (Newtons per square meter) P=0.613V^{2}.

13. Drag is the force that air exerts on the building.
The standard drag coefficient for a long cylinder tube is 1.2 and for a
short cylinder is 0.8.
The drag coefficient has no units.

15. For example, let’s say you want to determine the wind
load on a building that is 3 feet long with a diameter of 0.5
inches in a gust of 70f/s winds. Start by estimating the
projected area.

16. In this case, A=dw=(3ft)(0.5in)(1ft/12in)=0.125ft^{2}
Calculate the wind
pressure: P=0.00256V^{2}=0.00256(70^{2})=12.5psf}.
For a short cylinder the coefficient of drag is 0.8.
Plugging into the
equation: F=APCd=(0.125ft^{2})(12.5psf)(0.8)=1.25lbs.
}
1.25 lbs.