ASCE 7-16 Wind

[JAE]

Is it just us or are the roof C&C wind charts a complete mess?

The charts show a scale value on the left side but then dictate an equation based on THETA (roof slope) that when plugged in to the equation don't come even close to the value of the line on the chart scale?
(Section 30.3 for example).



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[ilyas415]

Hi JAE,

I did a quick check on one of them, and they seem OK to me.

The figures themselves are based on 45 degree slopes.
Also, please be careful not to trip up on the signs (-/+).

Maybe there is some curve which is inconsistent?

Thanks

-------------
Ilyas

 

[Ron]

ASCE 7 gets more unintelligible with each revision.

 

[chicopee]

results in red color are correct.
perhaps you have used radian value instead of the 30 degrees value in the two equations.

 

[Ron]

The chart and equation are only the same if the slope is 45 deg, which is rare for a roof. Any other value of theta results in a different value than shown on the chart.

 

[bones206]

I'll pile on... the charts for canopy C&C pressures have no labels or equations. The user must resort to eyeballing the values on the curves. That's frustrating.