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5/27/2018 ASCE705Wind
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"ASCE705W" --- ASCE 7-05 CODE WIND ANALYSIS PROGRAM
Program Description:
"ASCE705W" is a spreadsheet program written in MS-Excel for the purpose of wind loading analysis for buildings
and structures per the ASCE 7-05 Code. Specifically, wind pressure coefficients and related and required
parameters are selected or calculated in order to compute the net design wind pressures.
This program is a workbook consisting of nine (9) worksheets, described as follows:
Worksheet Name Description
Doc This documentation sheet
Simplified Analysis using simplified method for low-rise buildings with h
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - MWFRS and Components/Cladding
Per ASCE 7-05 Code for Low-Rise, Enclosed Buildings with h
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D 0 00
"ASCE705W.xls" Program
Version 1.0
(continued)
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"ASCE705W.xls" Program
Version 1.0
Total Design MWFRS Horizontal Load (kips)
Transverse Longitudinal
Load Case 1 Load Case 2 Min. Load Load Case 1 Load Case 2 Min. Load
8.97 --- 11.59 7.12 --- 6.97
Formulas:
Ph(Trans) = ((Pc*(L-4*a)+Pa*4*a)*he+(Pd*(L-4*a)+Pb*4*a)*(hr-he))/1000
Ph(Trans)(min) = P(min)*L*hr/1000 , where: P(min) = 10.0 psf on projected area
Ph(Long) = (Pa*(hr+he)/2*4*a+Pc*((hr+he)/2*W-(hr+he)/2*4*a))/1000
Ph(Long)(min) = P(min)*W*(hr+he)/2/1000 , where: P(min) = 10.0 psf on full area
Components & Cladding Net Pressures, ps(psf) pnet = l*Kzt*I*pnet30
Item Location Zone Pos. (+) Neg. (-) (pnet30 from Fig. 6-3)Wall 4 = interior zone of wall 4 12.70 -13.95
5 = end zone of wall 5 12.70 -15.80
1 = interior zone of roof 1 4.70 -13.30
Roof Joist 2 = end zone of roof 2 4.70 -15.80
3 = corner zone of roof 3 4.70 -15.80
Roof Overhang 2 = end zone of o.h. 2 --- ---
3 = corner zone of o.h. 3 --- ---
Notes: 1. For Method 1: Simplified Procedure of Section 6.4 to be used for an enclosed low-rise building
to determine the design wind loads, all of the following eight conditions of 6.4.1.1 must be met:
a. Building is a simple diaphragm building, in which wind loads are transmitted through floor
and roof diaphragms to the vertical Main Wind-Force Resisting System (MWFRS).
b. Building is a low-rise building where mean roof height, h
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"ASCE705W.xls" Program
Version 1.0
MWFRS - Wind Zones
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - Main Wind-Force Resisting SystemPer ASCE 7-05 Code for Enclosed or Partially Enclosed Buildings
Using Method 2: Analytical Procedure (Section 6.5) for Low-Rise BuildingsJob Name: Subject:
Job Number: Originator: Checker:
Input Data:
Wind Speed, V = 90 mph (Wind Map, Figure 6-1)
Bldg. Classification = II (Table 1-1 Occupancy Cat.)
Exposure Category = C (Sect. 6.5.6)
Ridge Height, hr = 53.33 ft. (hr >= he)Eave Height, he = 20.00 ft. (he 10 deg.)
Check Criteria for a Low-Rise Building:
1. Is h
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"ASCE705W.xls" Program
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MWFRS Wind Load for Transverse Direction MWFRS Wind Load for Longitudinal Direction
Surface GCpf p = Net Pressures (psf) Surface *GCpf p = Net Pressures (psf)
(w/ +GCpi) (w/ -GCpi) (w/ +GCpi) (w/ -GCpi)
Zone 1 0.52 6.08 12.58 Zone 1 0.40 3.97 10.47
Zone 2 -0.69 -15.71 -9.21 Zone 2 -0.69 -15.71 -9.21
Zone 3 -0.47 -11.71 -5.21 Zone 3 -0.37 -9.93 -3.43
Zone 4 -0.42 -10.75 -4.25 Zone 4 -0.29 -8.49 -1.99
Zone 5 -0.45 -11.38 -4.88 Zone 5 -0.45 -11.38 -4.88
Zone 6 -0.45 -11.38 -4.88 Zone 6 -0.45 -11.38 -4.88
Zone 1E 0.78 10.84 17.34 Zone 1E 0.61 7.77 14.27
Zone 2E -1.07 -22.57 -16.07 Zone 2E -1.07 -22.57 -16.07
Zone 3E -0.67 -15.41 -8.91 Zone 3E -0.53 -12.82 -6.32Zone 4E -0.62 -14.41 -7.91 Zone 4E -0.43 -11.02 -4.51
*Note: Use roof angle q= 0 degrees for Longitudinal Direction.
For Trans. when GCpf is neg. in Zones 2/2E: For Long. when GCpf is neg. in Zones 2/2E:
Zones 2/2E dist. = 50.00 ft. Zones 2/2E dist. = 50.00 ft.
Remainder of roof Zones 2/2E extending to ridge line shall use roof Zones 3/3E pressure coefficients.
MWFRS Wind Load for Transverse, Torsional Case MWFRS Wind Load for Long., Torsional Case
Surface GCpf p = Net Pressure (psf) Surface GCpf p = Net Pressure (psf)(w/ +GCpi) (w/ -GCpi) (w/ +GCpi) (w/ -GCpi)
Zone 1T --- 1.52 3.14 Zone 1T --- 0.99 2.62
Zone 2T --- -3.93 -2.30 Zone 2T --- -3.93 -2.30
Zone 3T --- -2.93 -1.30 Zone 3T --- -2.48 -0.86
Zone 4T --- -2.69 -1.06 Zone 4T --- -2.12 -0.50
Notes: 1. For Transverse, Longitudinal, and Torsional Cases:
Zone 1 is windward wall for interior zone. Zone 1E is windward wall for end zone.
Zone 2 is windward roof for interior zone. Zone 2E is windward roof for end zone. Zone 3 is leeward roof for interior zone. Zone 3E is leeward roof for end zone.
Zone 4 is leeward wall for interior zone. Zone 4E is leeward wall for end zone.
Zones 5 and 6 are sidewalls.
Zone 1T is windward wall for torsional case Zone 2T is windward roof for torsional case
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"ASCE705W.xls" Program
Version 1.0
Low-Rise
Buildings
h
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - Main Wind-Force Resisting SystemPer ASCE 7-05 Code for Enclosed or Partially Enclosed Buildings
Using Method 2: Analytical Procedure (Section 6.5) for Buildings of Any HeightJob Name: Subject:
Job Number: Originator: Checker:
Input Data:
Wind Direction = Normal (Normal or Parallel to building ridge)
Wind Speed, V = 120 mph (Wind Map, Figure 6-1)
Bldg. Classification = II (Table 1-1 Occupancy Cat.)
Exposure Category = B (Sect. 6.5.6)Ridge Height, hr = 157.00 ft. (hr >= he)
Eave Height, he = 157.00 ft. (he
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"ASCE705W.xls" Program
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Normal to Ridge Wind Load Tabulation for MWFRS - Buildings of Any Height
Surface z Kz qz Cp p = Net Design Press. (psf)
(ft.) (psf) (w/ +GCpi) (w/ -GCpi)
Windward Wall 0 0.57 18.01 0.80 5.45 18.13
15.00 0.57 18.01 0.80 5.45 18.13
20.00 0.62 19.55 0.80 6.46 19.14
25.00 0.67 20.84 0.80 7.30 19.98
30.00 0.70 21.95 0.80 8.03 20.71
35.00 0.73 22.94 0.80 8.68 21.36
40.00 0.76 23.83 0.80 9.26 21.94
45.00 0.79 24.65 0.80 9.80 22.48
50.00 0.81 25.40 0.80 10.29 22.97
55.00 0.83 26.10 0.80 10.75 23.43
60.00 0.85 26.76 0.80 11.18 23.86
70.00 0.89 27.97 0.80 11.97 24.65
80.00 0.93 29.05 0.80 12.68 25.36
90.00 0.96 30.05 0.80 13.33 26.01
100.00 0.99 30.97 0.80 13.93 26.61
120.00 1.04 32.62 0.80 15.01 27.70
140.00 1.09 34.09 0.80 15.98 28.66
For z = hr: 157.00 1.12 35.23 0.80 16.72 29.40
For z = he: 157.00 1.12 35.23 0.80 16.72 29.40For z = h: 157.00 1.12 35.23 0.80 16.72 29.40
Leeward Wall All - - -0.50 -20.75 -8.07
Side Walls All - - -0.70 -26.52 -13.84
Roof (zone #1) cond 1 1 04 36 32 23 64
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"ASCE705W.xls" Program
Version 1.0
Determination of Gust Effect Factor, G:
Is Building Flexible? No f >=1 Hz.
1: Simplified Method for Rigid Building
G = 0.850
Parameters Used in Both Item #2 and Item #3 Calculations (from Table 6-2):
a^ = 0.143
b^ = 0.84
a(bar) = 0.250
b(bar) = 0.45
c = 0.30
l = 320 ft.
e(bar) = 0.333
z(min) = 30 ft.
Calculated Parameters Used in Both Rigid and/or Flexible Building Calculations:
z(bar) = 94.20 = 0.6*h , but not < z(min) , ft.
Iz(bar) = 0.252 = c*(33/z(bar)) (1/6) , Eq. 6-5Lz(bar) = 453.94 = l*(z(bar)/33)^(e(bar)), Eq. 6-7
gq = 3.4 (3.4, per Sect. 6.5.8.1)
gv = 3.4 (3.4, per Sect. 6.5.8.1)
gr = 4.218 = (2*(LN(3600*f)))^(1/2)+0.577/(2*LN(3600*f)) (1/2) , Eq. 6-9
Q = 0.805 = (1/(1+0.63*((B+h)/Lz(bar))^0.63))^(1/2) , Eq. 6-6
2: Calculation of G for Rigid Building
G = 0.818 = 0.925*((1+1.7*gq*Iz(bar)*Q)/(1+1.7*gv*Iz(bar))) , Eq. 6-4
3: Calculation of Gf for Flexible Building
b= 0.030 Damping Ratio
Ct = 0.020 Period Coefficient
T = 0 887 = Ct*h^(3/4) sec (Approximate fundamental period)
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"ASCE705W.xls" Program
Version 1.0
Figure 6-9 - Design Wind Load Cases of MWFRS for Buildings of All Heights
Case 1: Full design wind pressure acting on the projected area perpendicular to each principal axis of
the structure, considered separately along each principal axis.
Case 2: Three quarters of the design wind pressure acting on the projected area perpendicular to each
principal axis of the structure in conjunction with a torsional moment as shown considered
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - Wall Components and CladdingPer ASCE 7-05 Code for Buildings of Any Height
Using Method 2: Analytical Procedure (Section 6.5)Job Name: Subject:
Job Number: Originator: Checker:
Input Data:
Wind Speed, V = 90 mph (Wind Map, Figure 6-1)
Bldg. Classification = II (Table 1-1 Occupancy Category)
Exposure Category = C (Sect. 6.5.6)
Ridge Height, hr = 53.33 ft. (hr >= he)Eave Height, he = 20.00 ft. (he 10 deg.)
Wall External Pressure Coefficients, GCp:
GCp Zone 4 Pos. = 0.77 (Fig. 6-11A)GCp Zone 5 Pos. = 0.77 (Fig. 6-11A)
GCp Zone 4 Neg. = -0.87 (Fig. 6-11A)
GCp Zone 5 Neg. = -0.93 (Fig. 6-11A)
& C ff GC ( )
q o
L
B
hr
heh
Plan
Elevation
L
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"ASCE705W.xls" Program
Version 1.0
Wind Load Tabulation for Wall Components & Cladding
Component z Kh qh p = Net Design Pressures (psf)
(ft.) (psf) Zone 4 (+) Zone 4 (-) Zone 5 (+) Zone 5 (-)
Girt 0 1.02 18.06 17.11 -18.91 17.11 -20.13
15.00 1.02 18.06 17.11 -18.91 17.11 -20.13
20.00 1.02 18.06 17.11 -18.91 17.11 -20.13
25.00 1.02 18.06 17.11 -18.91 17.11 -20.13
30.00 1.02 18.06 17.11 -18.91 17.11 -20.13
35.00 1.02 18.06 17.11 -18.91 17.11 -20.13
40.00 1.02 18.06 17.11 -18.91 17.11 -20.13
45.00 1.02 18.06 17.11 -18.91 17.11 -20.13
50.00 1.02 18.06 17.11 -18.91 17.11 -20.13
For z = hr: 53.33 1.02 18.06 17.11 -18.91 17.11 -20.13
For z = he: 20.00 1.02 18.06 17.11 -18.91 17.11 -20.13For z = h: 36.67 1.02 18.06 17.11 -18.91 17.11 -20.13
Notes: 1. (+) and (-) signs signify wind pressures acting toward & away from respective surfaces.
2 Width of Zone 5 (end zones) 'a' = 14 67 ft
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"ASCE705W.xls" Program
Version 1.0
Wall Components and Cladding:
Wall Zones for Buildings with h
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - Roof Components and CladdingPer ASCE 7-05 Code for Bldgs. of Any Height with Gable Roof
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"ASCE705W.xls" Program
Version 1.0
Wind Load Tabulation for Roof Components & Cladding
Component z Kh qh p = Net Design Pressures (psf)
(ft.) (psf) Zone 1,2,3 (+) Zone 1 (-) Zone 2 (-) Zone 3 (-)
Joist 0 1.02 18.06 8.67 -17.70 -24.92 -39.37
15.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
20.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
25.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
30.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
35.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
40.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
45.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
50.00 1.02 18.06 8.67 -17.70 -24.92 -39.37
For z = hr: 53.33 1.02 18.06 8.67 -17.70 -24.92 -39.37
For z = he: 20.00 1.02 18.06 8.67 -17.70 -24.92 -39.37For z = h: 36.67 1.02 18.06 8.67 -17.70 -24.92 -39.37
Notes: 1. (+) and (-) signs signify wind pressures acting toward & away from respective surfaces.
2 Width of Zone 2 (edge) 'a' = 14 67 ft
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"ASCE705W.xls" Program
Version 1.0
Roof Components and Cladding:
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - Chimneys, Stacks, and Vertical TanksPer ASCE 7-05 Code for Cantilevered Structures Classified as Other Structures
Job Name: Subject:
Job Number: Originator: Checker:
Input Data:
V = 90 mph (Wind Map, Figure 6-1)
Class. = II (Occupancy Category form Table 1-1)
Exposure = B (Exposure Category from Sect. 6.5.6)
Kzt = 1.00 (Topographic Factor from Sect. 6.5.7)h = 80.00 ft. (Height of Stack/Tank itself)
Hb = 0.00 ft. (Ht. of Stack/Tank Base Above Ground)
D = 20.00 ft. (Diameter or Width of Surface Normal to Wind)
Shape? Round (Round, Hexagonal, or Square)
b= 0.010 (Damping Ratio = 0.010-0.070) Elevation
Ct = 0.0412 (Period Coefficient = 0.020-0.035)
Kd = 0.95 (Direct. Factor, Table 6-4) Wind Load Tabulation for Stack / Tank
Cf = 0.700 (Force Coef. from Fig. 6-21) z Kz qz p=qz*G*Cf F=qz*G*Cf*D
(ft.) (psf) (psf) (lb/ft)0.00 0.57 11.32 7.76 155.28
Resulting Parameters and Coefficients: 5.00 0.57 11.32 7.76 155.28
10.00 0.57 11.32 7.76 155.28
If z < 15 then: Kz = 2.01*(15/zg)^(2/a) 15.00 0.57 11.32 7.76 155.28
If z >= 15 then: Kz = 2.01*(z/zg)^(2/a) 20.00 0.62 12.29 8.43 168.58
a= 7.00 (Table 6-2) 25.00 0.67 13.10 8.98 179.68
zg = 1200 (Table 6-2) 30.00 0.70 13.80 9.46 189.28
I= 1.00 (Table 6-1) (Import. Factor) 35.00 0.73 14.42 9.89 197.81
h/D = 4.000 40.00 0.76 14.98 10.27 205.50freq., f = 0.907 Hz. (f < 1) Flexible 45.00 0.79 15.50 10.63 212.53
G = 0.980 (Gust Factor, Sect. 6.5.8) 50.00 0.81 15.97 10.95 219.03
55.00 0.83 16.41 11.25 225.07
Ground
D
h
Hb >= 0
Wind
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"ASCE705W.xls" Program
Version 1.0
Determination of Gust Effect Factor, G:
Flexible? Yes f < 1 Hz.
1: Simplified Method for Rigid Structure
G = N.A.
Parameters Used in Both Item #2 and Item #3 Calculations (from Table 6-2):
a^ = 0.143
b^ = 0.84
a(bar) = 0.250
b(bar) = 0.45
c = 0.30
l = 320 ft.
e(bar) = 0.333
z(min) = 30 ft.
Calculated Parameters Used in Both Rigid and/or Flexible Structure Calculations:
z(bar) = 48.00 = 0.6*h , but not < z(min) , ft.
Iz(bar) = 0.282 = c*(33/z(bar))^(1/6) , Eq. 6-5
Lz(bar) = 362.57 = l*(z(bar)/33)^(e(bar)), Eq. 6-7
gq = 3.4 (3.4, per Sect. 6.5.8.1)
gv = 3.4 (3.4, per Sect. 6.5.8.1)
gr = 4.166 = (2*(LN(3600*f)))^(1/2)+0.577/(2*LN(3600*f)) (1/2) , Eq. 6-9
Q = 0.884 = (1/(1+0.63*((B+h)/Lz(bar))^0.63))^(1/2) , Eq. 6-6
2: Calculation of G for Rigid Structure
G = N.A. = 0.925*((1+1.7*gq*Iz(bar)*Q)/(1+1.7*gv*Iz(bar))) , Eq. 6-4
3: Calculation of Gf for Flexible Structure
b= 0.010 Damping Ratio
Ct = 0.041 Period Coefficient
T = 1 102 = Ct*h^(3/4) sec (Approximate fundamental period)
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"ASCE705W.xls" Program
Version 1.0
WIND LOADING ANALYSIS - Open Structures without RoofsPer ASCE 7-05 Code
Using Method 2: Analytical Procedure (Section 6.5) for Other Structures of Any Height
Job Name: Subject:
Job Number: Originator: Checker:
Input Data:
Resulting Parameters and Coefficients:
Wind Speed, V = 90 mph
Class., Occ. Category = III (Table 1-1) If z < 15 then: Kz = 2.01*(15/zg)^(2/a)
Exposure Category = C (Sect. 6.5.6) If z >= 15 then: Kz = 2.01*(z/zg)^(2/a)
Topo. Factor, Kzt = 1.00 (Sect. 6.5.7) a= 9.50 (Table 6-2)
Height of Structure, h = 125.00 ft. zg = 900 (Table 6-2)Structure Width, B = 150.00 ft. (normal to wind) I= 1.15 (Table 6-1)
Structure Length, L = 100.00 ft. (parallel to wind) freq., f = 1.337 Hz. (f >=1) Rigid
Damping Ratio, b= 0.010 (0.010 to 0.070) G = 0.850 (Gust Factor, Sect. 6.5.8)
Period Coefficient, Ct = 0.0200 (0.020 to 0.035)
Direct. Factor, Kd = 0.85 (Table 6-4) Velocity Pressure (Sect. 6.5.10, Eq. 6-15):
qz = 0.00256*Kz*Kzt*Kd*V^2*I
Note: Per Code Section 6.1.4.1, design wind force for open Net Design Wind Pressures (Sect. 6.5.15):
buildings and other structures shall not be less than 10 psf p = qz*G*Cf (psf), where 'qz' is evaluated at
multiplied by the area, 'Af', the area normal to wind direction. height 'z' of the centroid of projected area.
Open Structure - Net Design Wind Pressures, p
Force Coefficient, Cf
z Kz qz qz*G 1.20 1.60 1.80 2.00
(ft.) (psf) (psf) p p p p
(psf) (psf) (psf) (psf)
0 0.85 17.21 14.63 17.55 23.40 26.33 29.25
15 0.85 17.21 14.63 17.55 23.40 26.33 29.25
20 0.90 18.28 15.54 18.65 24.86 27.97 31.08
25 0.95 19.16 16.29 19.54 26.06 29.31 32.5730 0.98 19.91 16.92 20.31 27.08 30.46 33.85
35 1.01 20.57 17.48 20.98 27.97 31.47 34.96
40 1.04 21.15 17.98 21.58 28.77 32.36 35.96
45 1 07 21 68 18 43 22 12 29 49 33 18 36 86
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"ASCE705W.xls" Program
Version 1.0
Determination of Gust Effect Factor, G:
Flexible? No f >=1 Hz.
1: Simplified Method for Rigid Structure
G = 0.85
Parameters Used in Both Item #2 and Item #3 Calculations (from Table 6-2):
a^ = 0.105
b^ = 1.00
a(bar) = 0.154
b(bar) = 0.65c = 0.20
l = 500 ft.
e(bar) = 0.200
z(min) = 15 ft.
Calculated Parameters Used in Both Rigid and/or Flexible Structure Calculations:
z(bar) = 75.00 = 0.6*h , but not < z(min) , ft.
Iz(bar) = 0.174 = c*(33/z(bar))^(1/6) , Eq. 6-5
Lz(bar) = 589.22 = l*(z(bar)/33)^(e(bar)), Eq. 6-7
gq = 3.4 (3.4, per Sect. 6.5.8.1)gv = 3.4 (3.4, per Sect. 6.5.8.1)
gr = 4.258 = (2*(LN(3600*f)))^(1/2)+0.577/(2*LN(3600*f))^(1/2) , Eq. 6-9
Q = 0.848 = (1/(1+0.63*((B+h)/Lz(bar))^0.63))^(1/2) , Eq. 6-6
2: Calculation of G for Rigid Structure
G = 0.855 = 0.925*((1+1.7*gq*Iz(bar)*Q)/(1+1.7*gv*Iz(bar))) , Eq. 6-4
3: Calculation of Gf for Flexible Structure
b= 0.010 Damping RatioCt = 0.020 Period Coefficient
T = 0.748 = Ct*h^(3/4) , sec. (Period)
f = 1.337 = 1/T , Hz. (Natural Frequency)
V(fps) = N A = V(mph)*(88/60) ft /sec
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"ASCE705W.xls" Program
Version 1.0
Other Structures - Method 2 All Heights
Figure 6-22 Force Coefficients Open Signs &
Cf Lattice Frameworks Flat-Sided Rounded Members
Members D*SQRT(qz) 2.5
< 0.1 2.0 1.2 0.8
0.1 to 0.29 1.8 1.3 0.9
0.3 to 0.7 1.6 1.5 1.1
Notes: 1. Signs with openings comprising 30% or more of the gross area are classified as open signs.
2. The calculation of the design wind forces shall be based on the area of all exposed members
and elements projected on a plane normal to the wind direction. Forces shall be assumed to
act parallel to the wind direction.
3. The area 'Af' consistent with these force coefficients is the solid area projected normal to the
wind direction.
4. Notation: e= ratio of solid area to gross area
D = diameter of a typical round member, in feet.
qz = velocity pressure evaluated at height 'z' above ground in psf.
Other Structures - Method 2 All Heights
Figure 6-23 Force Coefficients
Cf Trussed TowersOpen Structures
Tower Cross Section Cf
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FIGURE 6-1: Basic Wind Speed
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FIGURE 6-1a: Western Gulf of Mexico Hurricane Coastline
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FIGURE 6-1b: Eastern Gulf & Southeastern U.S. Hurricane Coastline
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FIGURE 6-1c: Mid and Northern Atlantic Hurricane Coastline