jabacus - Wind on multi-span gable roofs with a slope between 10 and 45 degrees for C&C

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

Climatic Data

Location

Province:

Reference Velocity Pressure

Factors

Importance factor

Category:

Limit state:

Exposure Factor

Terrain:

Height, h:

m (Reference height in meters above grade)

Topographic Factor

C_t:

Internal pressure

Category, C_pi:

Midheight of dominant opening (for C_ei)

Midheight, h_i:

m (leave empty if no dominant opening.)

Building

Roof pitch:

/12

Tributary Area, A:

m²

End-zone width, z

(If H or the least horizontal dimension are left blank, z will not be calculated.)

Building Height, H:

m (Height of building at eave)

Least horizontal dim:

Region

Region 'c'

Region 'r'

Region 's'

Factors

User input values:
q: 1kPa
Importance Factor, ULS: I_w = 1.0
C_e = (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	C_pC_g	p_e (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

C_gi = 2

C_pi = -0.45 to 0.3

Reference height (max H/2 or 6m)= 6 m
C_ei = (h_i/10)^0.2 (but not less than 0.9) = 0.9

p_i = I_w*q*C_e*C_t*C_gi*C_pi
p_i = -0.81kPa to 0.54kPa

Combined Wind Pressure

Zone	C_pi=-0.45 p (kPa)	C_pi=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

This information must be read or used in conjunction with Part 4 of the NBC 2020. In the event of discrepancies, Part 4 of the NBC 2020 shall govern.