Wind Pressure question

[Humble Bumble Bee]

Where is wind pressure the greatest?
From studying Thaddeus, I thought the sides of a building have the greatest pressure (neg), followed by the windward face (pos), and the leeward face has the least amount of pressure (neg).

Mitalski has this question:
When considering a building structure being acted on by wind, which area of the exterior wall components will receive the greatest wind pressures?

a.the windward wall ends / corners (at the intersection of the side walls)
b.the windward wall, near its middle; away from the corners
c.the leeward wall ends / corners (at the intersection of the side walls)
d.the leeward wall, near its middle; away from the corners

The answer is C, Leeward wall ends/corners have the greatest wind pressures. I'm so confused now. Please help.

[caslem82]

Doesn't the Equals program (Mitalski questions) provide an explanation when you get a wrong answer? If you are on the question hit the check button at the bottom and the explanation shows up.

[Mike-SE]

The general formula for wind are:

qz = 0.00256*Kz*Kzt*Kd*(V^2)*I
p = (q*GCp) - (q*GCpi)
q= qz for load to the windward wall
q= qh for load to the leeward wall

z is the height at which you are calculating the pressure
h is the mean roof height.
For the windward side the pressure varies, minimum at the bottom and maximum at top (where z = h)
For the leeward side the pressure is constant the entire height of the building since h is a constant value.
At the roof, leeward and windward pressures are the same. Below the roof the leeward is always greater than the windward

[tweater5]

I believe that the wind force is strongest at the courners on the leeward side.
In general, all corners of a building, vertical or horizontal, recieve more force than the middle of a wall. However, the corners at the leeward side recieves the most.

[Humble Bumble Bee]

Thanks Tweater5! Very helpful.

Caslem82, the reason I posted the question is because the Mitalski answer and explanation did not line up with what I had gathered from other sources. Hence, my confusion.

[k4dm0nky]

I agree with C as the correct answer. His wind lecture further explains why.

[architect23]

Wouldn't the corner of a windward facade receive most wind pressure? And, to take it further, what if the windward facade was at a greater height than leeward facade?

[introversed]

To worsen the confusion a little more, here's a screenshot from the FEMA/AIA wind guide:

Fema wind.JPG

It shows the middle of the windward wall receiving the most wind pressure, even though the guide also states that corners see more pressure than the middle. And then there's the question mentioned here which answers "leeward corner"

The conflicting information makes me want to tear my hair out.

[architect23]

Yes, this is ridiculous!!

Humble says below:
"From studying Thaddeus, I thought the sides of a building have the greatest pressure (neg), followed by the windward face (pos), and the leeward face has the least amount of pressure (neg)."

I thought Thaddeus viewpoint was windward facade is most pressure, as it is positive. I would think negative forces would be least? Ah, this is confusing. Can anyone shed light? I'll repost the question.

Mitalski has this question:
When considering a building structure being acted on by wind, which area of the exterior wall components will receive the greatest wind pressures?

a.the windward wall ends / corners (at the intersection of the side walls)
b.the windward wall, near its middle; away from the corners
c.the leeward wall ends / corners (at the intersection of the side walls)
d.the leeward wall, near its middle; away from the corners

The answer is C, Leeward wall ends/corners have the greatest wind pressures.