Wind on multi-span gabled roofs with a slope between 10 and 45 degrees for C&C
Figure 4.1.7.6.-F (NBC2020)
v1.0.0
Factors
User input values:
q: 1kPa
Importance Factor, ULS: Iw = 1.0
Ce = (h/10)0.2 (but not less than 0.9) = 0.9
Roof slope: 26.57 degrees
q: 1kPa
Importance Factor, ULS: Iw = 1.0
Ce = (h/10)0.2 (but not less than 0.9) = 0.9
Roof slope: 26.57 degrees
External Wind Pressure
Using figure for multi-span gable roofs with slopes between 10 and 30 degrees.
Zone | CpCg | pe (kPa) |
---|---|---|
c- | -5 | -4.5 |
r- | -3 | -4.5 |
s- | -3.5 | -3.15 |
s'- | -4.2 | -3.78 |
c+ | 1.1 | 0.99 |
r+ | 1.1 | 0.99 |
s+ | 1.1 | 0.99 |
Internal Wind Pressure
Cgi = 2
Cpi = -0.45 to 0.3
Cei = (hi/10)0.2 (but not less than 0.9) = 0.9
pi = Iw*q*Ce*Ct*Cgi*Cpi
pi = -0.81kPa to 0.54kPa
Combined Wind Pressure
Zone | Cpi=-0.45 p (kPa) | Cpi=0.3 p (kPa) |
---|---|---|
c- | -3.69 | -5.04 |
c+ | 0.45 | 1.8 |
r- | -1.89 | -3.24 |
r+ | 0.45 | 1.8 |
s- | -2.34 | -3.69 |
s+ | 0.45 | 1.8 |
s'- | -2.97 | -4.32 |
End Zone Width
The end-zone width is the lesser of:• 10% of the least horizontal dimension = 0.1m
• 40% of the height of the building (H) = 0.4m
but not less than:
• 4% of the least horizontal dimension = 0.04m
• 1m
z = 1m