SPECIFICATION FOR THE DESIGN OF - Transcon Steel

Commentary on the Prescriptive Method for One and Two Family Dwellings - 2004 77
GCpf (ASCE Figure 6-4) CASE B
Roof Slope = 14.03 degrees
Are
a 1
Area
2
Area
3
Area
4
Area
5
Area
6
Area
1E
Area
2E
Area
3E
Area
4E
Area
5E
Area
6E
-0.45 -0.69 -0.37 -0.45 0.4 -0.29 -0.48 -1.07 -0.53 -0.48 0.61 -0.43
p (psf) - CASE A
Roof Slope = 14.03 degrees
Area 1 Area 2 Area 3 Area 4 Area 1E Area 2E Area 3E Area 4E
14.43 -19.08 -13.51 -12.15 19.83 -27.42 -17.68 -16.14
Are
a 1
-
13.8
2
Area
2
-
19.08
Area
3
-
12.06
p (psf) - CASE B
Roof Slope = 14.03 degrees
Area Area Area Area Area Area Area Area Area
4 5 6 1E 2E 3E 4E 5E 6E
-13.82 12.72 - -14.48 -27.42 -15.57 -14.48 17.33 -13.38
10.31
The above are based on corner length as follows:
0.4 x Building Height = 5.20 ft (height = 13.00 ft)
0.1 x min. Width = 3.20 ft
Not less than 3’
= 3.00 ft
a
= 3.20 ft
Corner Length = 2a = 6.40 ft
Roof Area 2 Factored Wind Load = 19.08 (1.6) = 30.52 psf
Roof Area 3 Factored Wind Load = 13.51 (1.6) = 21.62 psf
Factored Roof Dead Load = 0.9(15 psf) = 13.5 psf
Determine Forces in Walls
Side Walls
P = 12.72 + 10.31 = 23.03 psf (interior)
P = 17.33 + 13.38 = 30.71 psf (exterior, corner)
Force/Wall
⎡
=
⎢23.03psf
⎣
(1/ 2)(9')
32' −6.4'
⎤ ⎡
⎥ +
⎦
⎢23.03psf
2walls
⎣
⎡30.71psf
(3.2')(9') ⎤ ⎡(30.71psf
)(3.2')(0.8) ⎤
+ ⎢
⎥ +
⎣ 2 ⎦
⎢
⎣ 2 ⎥
⎦
Force/Wall = 2515 lb/side wall
(1/ 2)(32')(4')
2walls
⎤
⎥ −
⎦
⎡23.03
⎢
⎣
psf
(3.2')(0.8) ⎤
2 ⎥
⎦