Plans (2) /,26/5-iw 7Z'
•
CHAIN LINK FENCE
MANUFACTURERS INSTITUTE RECEIVED
DEC 17 2019
•
CITY OF TIGARD
CHAIN LINK FENCEBUILDINGDIVISION
WIND LOAD GUIDE FOR THE
SELECTION OF LINE POST AND
LINE POST SPACING
(WLG 2445)
FA C 5VE rt 1_,,E 75'.
:o_LacerY...Ate? kr,r,rf24 C)
TO 4:«i:M'EfiSb�ly IWRE
W k ytx a�'
•.\
i
04!
ekagE TWAT E:./E�RSA-:•£
EX'ERa'1^RAHJME''9 E'Efv*w5^a
-W
.w7'4eEE R
,^L ,riG
DTFE f<SRiG WiaES
R;Af.:'.OA'ED,
Updated January, 2018
Copyright (C) 2018 Chain Link Fence Manufacturers Institute All Rights Reserved.
10015 Old Columbia Road Suite B215
Columbia, MD 21046
Ph: 301-596-2583 Fax: 301-596-2594
Email: clfmihq@aol.com
www.chainlinkinfo.org
CHAIN LINK FENCE
9+G �� MANUFACTURERS INSTITUTE
4cTer rR\a�<
1/4
. s
For questions regarding the content or usage of the
information contained in this publication
contact our CLFMI Technical Support Team
Chain Link Fence Manufacturers Institute
10015 Old Columbia Road Suite B215
Columbia, MD 21046
Ph: 301-596-2583 Fax: 301-596-2594
Email: clfmihq@aol.com
Website: www.chainlinkinfo.org
DISCLAIMER
The Wind Load Guide for the Selection of Line Post Spacings for
Woven Wire Chain Link Fencing is published by the Chain Link Fence
Manufacturers Institute as a general information service in the selection
of spacing for fencing line posts for chain link fence systems. However,
because exposure, workmanship, soils, drainage, emplacement problems,
wind and other weather conditions may vary, even at various locations in
a single site, each application should be assessed by a qualified
professional engineer. Accordingly, no representation or warranty is
made, and none should be implied, respecting the suitability or adequacy of
the information in this Guide for any particular application, nor is this
Guide intended to establish industry "standards" respecting the selection
of spacing for fencing line posts, or for any purpose.
TABLEOF CONTENTS
• Introduction 1
• Factors Which Influence the Size and Spacing of Line Posts 2
• Figure 1, Line Post Spacing Details 3
• Methodology 4 to 5
• How to Use the Guide 6
• Examples 7 t 9
• Tables 10 to 22
• Table 1 ; Line Post Selection Guide for 105 MPH Wind
• Table 2; Line Post Selection Guide for 110 MPH Wind
• Table 3; Line Post Selection Guide for 120 MPH Wind
• Table 4; Line Post Selection Guide for 130 MPH Wind
• Table 5; Line Post Selection Guide for 140 MPH Wind
• Table 6; Line Post Selection Guide for 150 MPH Wind
• Table 7; Line Post Selection Guide for 160 MPH Wind
• Table 8; Line Post Selection Guide for 170 MPH Wind
• Table 9; Mesh and Fabric Size Coefficients "Cfi"
• Table 10; Wind Exposure Category Coefficients "Cf2"
• Table 11; Ice Exposure Effect Probability Coefficients "Cf3"
• Table 12; Line Post Material Properties Table
• Table 13; Wind Speed / Velocity Pressure Table
• Figure 26.5-1C, Minimum Basic Wind Speeds Map 23 to 24
• Appendix 25 to 32
• References 33
INTRODUCTION
The Chain Link Fence Manufacturers Institute (CLFMI) would like to acknowledge
Leonard Engineering, Inc. for the technical analysis of this Guide, as well as members of
the CLFMI Technical Committee, for their complete and thorough editing effort on the
orginal version. Also, further acknowledgement is extended to the American Society of
Civil Engineers (ASCE) for agreeing to the use of its copyrighted materials, CLFMI
wishes to extend special recognition to Charles Naegele, Chair of the CLFMI Technical
Committee, for his leadership in the production of this Guide.
This Guide is intended to provide background information in the forms of charts and
tables to assist fence designers and installers in the appropriate selection of fencing line
posts for chain link fencing. However, because conditions vary from site to site, the
information in the Guide should not be relied upon without the evaluation of a qualified
professional engineer.
PLEASE READ THE DISCLAIMER.
The Guide includes eight tables for the spacings of line posts exposed to wind speeds of
105 MPH up to and including 170 MPH. These tables are based on the applicable ASCE
7-10 wind load standards. The spacing values listed in the eight tables must be adjusted
using appropriate and selected coefficients to account for the size of the fabric gauge
and mesh size, wind exposure and the probability for the development of icing conditions
at that location. Moreover, the tables do not take into account wind speeds exceeding
170 MPH, which may occur in category 5 hurricanes, tornadoes, at high elevations, or as
the result of explosions.
Seven of the more commonly used fabric wire gage sizes and seven of the most
commonly used mesh sizes when used in any combination and acted upon by the
several sets of wind pressures (not wind speed or velocity) offers the user choices in the
selection and/or specifying line posts based on local wind conditions, economics,
aesthetics and functionality of other design criteria established for a specific application. It
should be noted that this guide is specifically designed for the use with chain link fence
systems only and is not intended for use with other fence designs.
The guide considers the following assumptions as being applicable in the design
analysis based on the wind loading criteria outlined in ASCE 7-10, "Minimum Load
Design Criteria for Buildings and Other Structures", Chapter 26, Wind Loads:
General Requirements and Chapter 29, Wind Loads on Other Structures and
Building Appurtenances—MWFRS.
• Wind is acting in a direction normal to the plane of the fencing fabric and
applied on the fabric side of the line post.
• Tension wire or rail at the base and top of the fence accommodates the
normal tensile loading being applied to take up vertical sag of the fence.
Additionally the line posts are considered to be embedded in the ground surface in
accordance with the minimum size and depth established according to the 2009
International Building Code and ASTM F567, "Standard Practice for Installation of
Chain Link Fence". All posts are considered to be embedded in concrete, minimum
2,500 psi, air-entrained, of a depth consistent with local soil types and conditions.
(1)
FACTORS WHICH INFLUENCE THE SIZE AND SPACING OF LINE POSTS*
• HEIGHT OF FENCE The height of the fence influences the actual amount of wind force that must be resisted by the
post and the required anchorage to the ground.The fence height times the line post spacing sets the total force acting on a
solid panel of the fence which is transferred to the line posts and then into the footing.
• STYLE AND SIZE OF FABRIC The style and size of fabric determines the net surface area of the solid fence panel
exposed to the wind pressure which in turn must possess adequate tensile strength to transfer the developed loading to the
supporting members of the fence assembly;i.e., line posts,top rail and base tension wire.
• MATERIAL STRENGTH AND SHAPE OF POST Material strength and shape of post determines the size of posts
and their spacing which will provide the required resistance to the maximum expected wind forces that may develop over the
anticipated normal life-span of the installation and to remain serviceable subsequent to the maximum wind event.
• UPDATED FOOTING ANALYSIS AS RELATED TO SOIL TYPE AND BEARING LOADS The type of soil that will
be encountered at the site of the fence installation will influence the post size and spacing by way of the passive soil pressures
that can reasonably be expected to resist the tendency for the line posts to overturn and also to remain in an essentially plumb
position after the wind event. For footing design criteria,it is advisable to contact a competent geotechnical professional for the
appropriate soils information at the particular site.The minimum depth of footings in accordance with ASTM F567 is 24"plus
an additional 3"for each one(1)foot of fence height over 4 feet.The 2009 International Building Code,(Eq. 18-1)is utilized
to determine the required footing embedment depth, up to a maximum embedment depth of 12'-0"below finish grade
VARIABLES AND DEFINITIONS for the FORMULA FOR DETERMING FOOTING DEPTH
P= Resultant concentrated wind force applied to post d = Diameter of post footing
c = Distance above top of footing at which "P" is applied to post S1 =Allowable lateral soil-bearing pressure
D = Post footing embedment depth below finish grade H = Fence post height above top of footing
D = 0.5A*{ 1 + [1 + (4.36* c)/A )]1/2)
A = 2.34P/S1*d
SEE THE CALCULATION EXAMPLE 3 ON PAGE(8) FOR AN ILLUSTRATION OF THIS ANALYSIS
The table listed below (which is also found on page 32 of this Guide) shows the Presumptive Soil Load Bearing Values for
calculations to determine footing sizes using this updated approach, which includes lateral as well as vertical factors.
TABLE 1805.2
PRESUMPTIVE LOAD-BEARING VALUES
LATERAL BEARING LATERAL SLIDING RESISTANCE
VERTICAL FOUNDATION PRESSURE
CLASS OF MATERIALS PRESSURE(psi) (psfff below natural grade) Coefficient of friction.' Cohesion)psf)b
1. Crvstalline bedrock 12,000 1.200 0 70 -
2. Sedimentary and fob-
4.000 400 0-35
ated rock
3 Sandy gravel and%or
3_000 200 0 35 -
gravel (GSA'and GP)
4. Sand silty sand,clayey
sand-silty gravel and
2.000 150 U.'S
clayey gravel (SW.SP.
SM. SC.GM and GC)
5 Clay. sandy clay_silty
clay,clayey-silt_ silt and 1.500 100 - 130
sandy silt (CL-ML
MHand CH)
For SI 1 pound per square foot=0.0479 kPa_ I pound per square foot per foot=0 157 kPa'm.
a Coefficient to be multiplied by the dead load.
b. Cohesion value to be multiplied by the contact areaas limited by Section 1306 3 2
• ACTUAL LATERAL SOIL BEARING PRESSURE(LSBP) DETERMINATION SHOULD BE DETERMINED AT
THE FENCE SITE BY APPROPRIATE MEANS. HOWEVER,WHEN USING TABULAR LSBP VALUES IN PLACE OF
ACTUAL SITE DATA, IT IS IMPORTANT TO KNOW THAT THEY ARE GENERALLY ADJUSTED UPWARD
DEPENDING ON THE DEPTH OF EMBEDMENT WHEN CALCULATING A FOOTING DEPTH. HOWEVER, THIS LSBP
INCREASE IN VALUE SHOULD ONLY BE APPLIED UNDER THE SUPERVISION OF A PROFESSIONAL THAT IS
KNOWLEDGEABLE AND FAMILIAR WITH THE CONDITIONS SPECIFIC TO THE SITE AND APPLICATION.
• WIND PRESSURE Wind pressure is the most dominant factor that influences the post size and spacing since it is
the only force that can reasonably be predicted and will be acting on the posts under normal conditions. Reference Table 13
for values of various wind speeds and pressures.Wind pressure in itself is further influenced by other factors; i.e.,
geographical region, exposure,topography and ground surface features in the local area.
*Reference Figure 1,"LINE POST (2)
FENCE SUPPORT SELECTION=
X NCI"INAL SPACING,_ a.) GALVANIZED STEEL PIPE.
�J dr
OF LINE POSTS = S b.) COLD ROLLED FORMED
1 mAx. RECOMMENDED ' STEEL 'C' SECTION.
� � SPACING . 10'-0" --1 .
,r
WIND DIRECTION - ALWAYS ASSUMED
I TO BE ACTING NOR-IAL TO PLANE OF
i FABRIC ;N DIRECTION TOWARD THE
FABRIC SIDE OF LINE POST.
WIND PRESSURE DETERMINED BY
I REGION, LOCATION, TOPCC RAPHY,
} SURFACE FEATURES AND EXPOSURE
I FOLLOWING .ASCE 7-10(FIGURE 26 5-1C)
t
1
FENCE FABRIC TOP RAIL OR TENSION WIRE
041~111M11~111~1174/011111111416'111111FirerW SC
}.X V*r >'. h>,, 1 LINE POST-SEE TABLE 12 FOR
.;'-'>'\''';','x'.','..xx ? u li x r
',';',Y,:..,',"fix,/, y .- SCHEDULE OF TYPES,SIZES,AND
f ; '',e`:.'...'..",' v •?;' v...../ x'� r' 1 MATERIALS OF POST.
.xh ''A. • ♦♦ ♦ 44104 04: %j. TENSION WIRE
-IcN.
GR..ND LEVEL
/ CIRCULAR CONCRETE FOOTINGS. EMBEDMENT
NOMINAL Z"`- 4 D DEPTH DEPENDENT ON TYPE OF SOIL THAT
/ \ CLEAR I EXISTS ON SITE.THE O.D.("D")OF THE FOOTING
LI \
u IS EXPRESSED AS 4(pd)OR 3(pd)(WHERE"pd"_
4 POST OD)DEPENDING ON THE SIZE OF THE
______ /1POST DIAMETER.
W I d Ref.ASTM F567 and 2009 IBC(Eq. 18-1)
� X
ASSUMPTIONS=
, a.) POSTS ARE SET IN CIRCULAR CONCRETE
, ~ / FOOTINGS USING 2500 P.5.1. AE. CONCRETE:
EMBEDMENT INTO GROUND ACCORDING TO
/ Ah PREVAILING GROUND CONDITIONS AND
, '� NV N� I c�f;AL PRACTICE
t a WIRE GAGE.
EFFECTIVE SURFACE AREA IN ONE Cl) SQUARE
FOOT OF FENCE PANEL THAT RECEIVES POSITIVE
EXTERNAL PRESSURE IS DETERMINED BY THE
NUMBER OF DIAMONDS FORMED IN THE AREA
AND THE DIAMETER OF THE FABRIC WIRES
(COATED OR UNCOATED)
F(C.�UR.E "1
LINE POST SPACING GUIPE PET4ILS
(3)
METHODOLOGY
The methodology applied to develop the tabular values of "S", the unmodified maximum spacings
of line post materials, sizes and shapes most commonly employed in the chain link fencing
industry, for the fence heights and wind speeds was based on wind loading criteria outlined in
ASCE 7-10, Chapter 26, Wind Loads: General Requirements and Chapter 29, Wind Loads
on Other Structures and Building Appurtenances—MWFRS, excerpts of which are
included in the Appendix of this Guide.
This application of the recommended loading criteria as it applies to fence construction takes into
consideration all factors that influence the wind forces applied to the primary force resisting
element of the fence; in this instance the line posts, which in-turn must transfer that loading to the
ground. This guide is based on the assumption of a solid panel of fencing and uses multiplication
factors for various percentages of free area of the fence panel.
To establish the magnitude of the wind force that will be acting on the line post, it must first be
established what the net surface area of the fence panel will be; i.e., the solid panel area, "h x S"
less the void spaces within the fence. The net surface area of the wire fabric is what the wind
force impinges on and is directed on to the post. Since the panel of the fence is essentially a
perforated plane, it is necessary to quantify the actual solid surface to void area. The area of wire
surface was determined by establishing the number of diamonds in a square foot of fabric and
totaling the length of wire in that area. This is the value used in combination with the computed wind
velocity pressures that when applied as a load to the fence post acting as a flagpole design; i.e., a
vertical cantilever, fixed at its base to the footing and ground.
Now with the value known for the wind velocity pressure that develops for each of the selected
ranges of the eight Wind Speed Classes of 105 MPH through 170 MPH acting under normal
• conditions for a Wind Exposure Category "B", these forces are then applied to the face area of the
fence panel assumed to be solid. With the height "H" of the fence known, the only variable that
needs to be established to set the total gross area "Ag" of the panel is the line post spacing "S".
The values of"S" were generated based on the loading applied to the post as a vertical cantilever,
in a similar fashion as the "classic" flagpole design.
Table 1 through Table 8 are set up for fence heights that range from 3 feet up to and including 20
feet and twenty-six combinations of line post sizes and types, in a solid panel configuration. The
"S" values were computed on the basis of their physical, material properties and formulas listed
in Table 12 with a limiting value based on the maximum allowable stress.
To account for the variations in the fabric wire sizes and sizes of mesh, Table 9 was developed
and lists the Coefficient "Cfi" which accounts for the variation and is based on a ratio of net area
to gross area of a solid panel for each of the commonly used styles employed in the industry.
(4)
The base program for the line post spacing was set up using the condition where Wind Exposure
Category "B" is the normal situation. To account for the other two Wind Exposure Categories, "C"
and "D", Table 10 was developed to list the Coefficient "Cf2" which is a ratio of the Wind Exposure
Coefficient "Kz" for Exposure "B" to the other two exposure coefficients as listed in ASCE 7-10,
Table 29.3-1.
In Table 11, Ice Effect Probability Coefficient "Cf3" is included in the guide and was set up using
arbitrary values to permit the designer the ability to make an intelligent decision relative to his
perception and experience as to the probability that a severe icing condition may develop
concurrent with the listed maximum wind speed for that particular geographical location for non-
solid fencing.
Figure 26.5-1C from ASCE 7-10 shows wind speed categories in the range of 105 MPH to 170
MPH, but also includes special wind speed regions and a 180 MPH wind speed for use in Guam.
This guide provides values of wind speeds that cover the entire range of velocities that may be
encountered in the continental United States and Hawaii but does not include Guam and will
require separate analysis to determine wind speeds in the special wind speed regions as
determined by local jurisdictions and/or case study. For any installations determined to have
intermediate wind speeds, it is acceptable to interpolate linearly.
The user of this guide is advised that he may want to consider use of the full allowable stress of
the material being employed which has a built-in Factor of Safety equivalent to 1.5; ie., 0.66 Fy,
Reference Table 12. The user may also want to consider the merits of using a higher maximum
allowable stress increase due to the fact that wind loadings usually may not be a sustained
condition for that specific location where the fence installation is being planned.
(5)
HOW TO USE THE GUIDE
For the fence fabric configuration and size of line post being considered, go to the appropriate table (Table
• 1,2,3, .... ,8) that closely agrees with the maximum anticipated wind speed designated by the local codes for
that geographical area where the fence installation is planned. From that table, find the value of"S" for the
line post size and height desired. This value of"S" must then be multiplied by correction coefficients that
account for the type, size and mesh of the wire fabric, "Cf1" from Table 9;Wind exposure category
coefficient, "Cf2" from Table 10; Icing effects probability coefficient, "Cf3" from Table 11.
The recommended post spacing S'= S X Cf1 x Cf2 x Cf3
EXAMPLEI:
Select a line post spacing for a 10' high Chain Link fence, constructed of#9 gage wire, having a mesh size
pattern of 1-3/4". The installation location is for a park in an urban location in the Eastern U. S., where the
wind exposure is considered " Exposure C".Assume the local governing code indicates that the maximum
wind speed for this application is 105 MPH; localized icing effects are considered to be moderate. One
possible line post material selection for this example is Group 1A, Schedule 40 steel pipe.
From Table 1,Wind Speed 105 MPH, fora 4.0" outside diameter pipe, the listed
"S" value for a 10' high fence is 3.6.
From Table 9,the Coefficient "Cf1", for a#9 gage, 1-3/4" mesh fabric = 6.4
• From Table 10, the Coefficient "Cf2", for a Wind Exposure Category C= 0.67
From Table 11, the Coefficient "Cf3", for Moderate Icing Effects = 0.85
Thus the recommended maximum spacing for the 4" outside diameter Schedule 40, steel pipe post for
the 10' high fence with a#9 gage wire and 1-3/4" mesh would be:
S'=SX Cf1 xCf2 xCf3 =3.6 x6.4x0.67 x0.85 =13.12'
The maximum recommended spacing would be 10'-0" c/c for the posts.
(6)
EXAMPLE2
For a situation where the Wind Velocity is other than for one of the eight listed tables of line post
spacings in the guide:
Select a line post size and spacing for a 16' high chain link fence installation for which the fabric is to be a#9
" gage - 1/2" mesh pattern. Assume the fence location is in an open terrain where the Wind Exposure
Category is"C" and the code listed maximum wind speed is 115 MPH; icing effects potential is
considered to be moderate.
From Table 9, the coefficient "Cfi" for mesh size and gage = 2.20
From Table 10, the coefficient "Cf2" for wind exposure "C" = 0.69
From Table 11, the coefficient "Cf3"for moderate icing effect = 0.85
From Table 2,for a 110 MPH wind and a 16' high fence, select a Trial
line post size spacing factor "S" =4.8 for a Group IA, 6-5/8" OD steel pipe.
For this arrangement the maximum spacing would be the result of 4.8 x 2.20 x
0.69 x 0.85 = 6.19' ; This may not be an economical or practical spacing.
Therefore try the spacing for a Group IA, 8-5/8" OD steel pipe where "S" = 9.70
whose maximum recommended spacing would be 9.70/4.8 x 6.19' = 12.51'.
Since the wind speed being evaluated is 115 MPH condition the recommended spacing
would be 110/115 x 12.51' = 11.97' or 10'- 0" on centers, which would be more
consistent with the usual standard spacing followed in the industry.
(7)
EXAMPLE3:
For a site location with a high wind condition and the design selection of an
appropriate footing size and depth:
Select a line post size, its spacing and footing for a 12' high chain link fence that will consist of a #9
gage-1-3/4" mesh fabric. Installation will be in Southern Florida in an open terrain with a wind
exposure category "C" and a maximum wind velocity of 150 MPH. Soil condition is assumed to be a
silty sand (Actual soil properties should be established by a qualified geotechnical engineer familiar
with local soil conditions).
From Table 6 for 150 MPH wind and under 12' high fence and a trial size
line post of Group IA, 4" outside diameter steel pipe "S" = 1.2
"Cfi" for the fabric size and gage = 6.4
"Cf2" for the wind exposure category= 0.67
"Cf3" for icing condition = 1.0
Thus the maximum spacing for the Group IA, 4" outside diameter pipe = 1.2 x 6.4 x
0.67 x 1.0 = 5.14'. This may not be an economical spacing; try another
trial size post.
Checking the spacing for a Group IA, 6-5/8" outside diameter pipe where
"S" =4.6, maximum spacing will be 4.6/1.2 x 5.14' = 19.7' use 10'-0".
For the 6-5/8" outside diameter line post, the minimum footing size is 3 x Pipe
outside diameter per ASTM F567 or 19.9"; however, it is recommended that
• footing size of 30" diameter be used. The minimum depth of footing
embedment in the silty sand soil is to be calculated as follows:
t.s • I foNe
til ;
+ . fir' _ E
LINEPOST FOOTING PRESSURE
Allowable lateral soil bearing pressure (Si) for silty sand = 150 psf*,
as determined from the 2009 International Building Code Table 1806.2
Presumptive Soil Load-Bearing Values. See Appendix, pg. 32.
(8)
EXAMPLE 3 (Continued):
Distance of applied force above footing "c" = 0.5H + 0.05H =0.55 x 12' = 6.60'
Applied Force "P" = (1/Cf1) x Net Area of Fence x Wind Pressure where Cf1 is the
Mesh and Fabric Size Coefficient from Table 9 and the Wind Pressure is the Design
Wind Pressure from Table 13.
P = (0.16 sf/sf) (120 sf) (45.99 lb/sf) = 883 lbs
Diameter of footing b =30" =2.50'
Solving for"D" D = 0.5A * { 1 + [ 1 + (4.36 * c ) /A ) ]h12} (2009 IBC Eq. 18-1)
where A = 2.34P/S1*b = 2.34 * ( 883 lbs )/ 150psf* 2.5
= 5.51
D = ( 0.5 )( 5.51 ) * { 1 + [ 1 + (4.36 * 6.60 /5.51 )]1/2 }
= 9.63'
AS ILLUSTRATED ABOVE THE CALCULATION FOR "D" PRODUCED A RESULT OF 9.63' USING
A VALUE OF 150 PSF FROM THE TABLE ON PAGE 2 AS THE ALLOWABLE LATERAL SOIL
BEARING PRESSURE (LSBP). HOWEVER AS INDICATED IN THE TEXT FOLLOWING THIS
TABLE AN UPWARD ADJUSTMENT OF THIS SOIL PROPERTY SHOULD ONLY BE DONE UNDER
THE SUPERVISION OF A KNOWLEDGEABLE PROFESSIONAL. IT ALSO BECOMES CLEAR THAT
WITHOUT INCREASING THE LSBP DUE TO EMBEDMENT DEPTH THE RESULTING "D"
CALCULATION (9.63')WILL BE OVERLY CONSERVATIVE WHICH IS EVIDENT IN THIS
EXAMPLE. FOR THIS SITUATION A MORE REASONABLE DEPTH FOR THE FOOTING CAN BE
DETERMINED WITH ASTM F567 WHICH REQUIRES A DEPTH OF 24" PLUS AN ADDITIONAL 3"
FOR EACH ONE (1) FOOT OF FENCE HEIGHT OVER 4 FEET:
ACCORDINGLY,
D= 24" + [(3" X(12' -4')] = 24" + 24" = 48"
(9)
TABLE 1
LINE POST SELECTION: WIND SPEED 105 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING,S(FEET)FOR USE IN EQUATION:S'=S X Cfl x Cf2 x Cf3
FENCE HEIGHT(FEET)
- LINE POST 3 1 3 .5 1 4 ; 5 6 1 7 1 8 1 9 1 10 1 11 12 1 13 1 14 15 f 16 1 17 1 18 1 19 1 20
SIZE IN I
Group IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
- 17/8" 5.5 4.0 3.0 1.9 1.2 ---- ---- ---- ----2 3/8" 9.6 7.0 5.3 3.4 2.3 1.6 1.2
2 7/8" 18.1 13.3 10.2 6.5 4.4 3.2 2.4 1.9 1.5 1.2 ---- ---- ---- ---- ---- ---- ---- ----3 1/2" 29.5 21.8 16.6 10.6 7.3 5.3 4.0 3.2 2.5 2.0 1.7 1.4 1.2 ---- ---- ---- ---- ----4" 41.0 30.1 23.0 14.7 10.2 7.5 5.7 4.4 3.6 2.9 2.4 2.0 1.7 1.5 1.2 1.1 ---- ----6 5/8" ---- ---- ---- 52.5 36.4 26.8 20.5 16.2 13.1 10.8 9.0 7.7 6.6 5.7 5.0 4.4 3.9 3.5 3.1
8 5/8" ---- ---- ---- ---- ---- 53.0 40.5 32.0 25.9 21.4 18.0 15.3 13.2 11.5 10.1 8.9 7.9 7.1 6.4
GROUP IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield strength)
1 7/8" 9.2 6.7 5.0 3.2 2.0
2 3/8" 16.0 11.7 8.8 5.7 3.8 2.7 2.0
2 7/8" 30.2 22.2 17.0 10.8 7.3 5.3 4.0 3.2 2.5 2.0 ---- ---- ---- ---- ---- --- ---- ----3 1/2" 49.2 36.0 27.7 17.7 12.2 8.8 6.7 5.3 4.2 3.3 2.8 2.3 2.0 ---- ---- ---- ---- ----4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ---- ----6 5/8" ---- ---- ---- ---- 60.7 44.7 34.2 27.0 21.8 18.0 ! 15.0 12.8 11.0 9.5 8.3 7.3 6.5 5.8 5.2 1
I 1
8 5/8" ---- ---- ---- ---- ---- ---- 67.5 53.3 43.2 35.7 30.0 25.5 22.0 19.2 16.8 14.8 13.2 11.8 10.7
GROUP IC:(ASTM F1043)Steel Pipe(50,000 psi yield)
1 5/8" 5.5 3.9 3.0 1.8 1.1
1 7/8" 7.9 5.8 4.3 2.7 1.7 1.2
2 3/8" 1 3.9 10.1 7.7 4.9 3.3 2.3 1.7 1.2
2 7/8" 25.0 18.4 14 8.9 6.1 4.4 3.3 2.5 2.0 1.5 1.2 ---- ---- ---- ---- ---- ---- ----3 1/2" 38.3 28.1 21.5 13.7 9.5 6.9 5.2 4.0 3.2 2.6 2.1 1.7 1.4 1.2 ---- ---- ---- ----4" 50.9 37.4 28.6 18.3 12.6 9.2 7.0 5.5 4.4 3.6 2.9 2.4 2.0 1.7 1.5 1.2 1.1 ----GROUP II:(ASTM F1043)High Strength Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x.105 5.9 4.3 3.3 2.0 1.3 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----1 7/8"x 1 5/8"x.121 10.0 7.3 5.6 3.5 2.3 1.6 1.2 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----2 1/4"x 1 5/8"x.121 11.6 8.5 6.4 4.0 2.7 1.9 1.3 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----3 1/4"x 2 1/2"x.130 26.6 20.9 15.8 9.9 6.6 4.6 3.2 2.3 1.6 1.1 ---- ---- ---- ---- ---- ---- ---- ----See Table 12 for post dimensions and material properties.
(10)
TABLE 2
LINE POST SELECTION: WIND SPEED 110 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING,$(FEET)FOR USE IN EQUATION:S'=S X Cfl x Cf2 x Cf3
FENCE HEIGHT(FEET)
. LINE POST 1 3 3.5 4 5 6 I 7 8 I 9 10 ! 11 i 12 1 13 14 15 16117 17 {{ 18 19 20
SIZE IN } I I I s I I
Group IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 5.3 3.9 2.9 1.8 1.2
2 3/8" 9.2 6.8 5.1 3.2 2.2 1.6 1.1
2 7/8" 17.5 12.8 9.8 6.2 4.3 3.1 2.3 1.8 1.4 1.1 ---
3 1/2" 28.4 20.9 16.0 10.2 7.0 5.1 3.9 3.0 2.4 2.0 1.6 1.3 1.1 ---
4" 39.6 29.0 22.2 14.2 9.8 7.2 5.5 4.3 3.4 2.8 2.3 1.9 1.6 1.4 1.2 1.0 ----
6 5/8" ---- ---- 50.7 35.2 25.8 19.7 15.6 12.6 10.4 8.7 7.4 6.4 5.5 4.8 4.3 3.8 3.4 3.0
8 5/8" ---- 51.1 39.1 30.9 25.0 20.6 17.3 14.8 12.7 11.1 9.7 8.6 7.6 6.8 6.2
GROUP IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield strength)
1 7/8" 8.8 6.5 4.8 3.0 2.0
2 3/8" 15.3 11.3 8.5 5.3 3.7 2.7 1.8
2 7/8" 29.2 21.3 16.3 10.3 7.2 5.2 3.8 3.0 2.3 1.8 ---
3 1/2" 47.3 34.8 26.7 17.0 11.7 8.5 6.5 5.0 4.0 3.3 2.7 2.2 1.8 ----
4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ----
6 5/8" ---- ---- ---- 84.5 58.7 43.0 32.8 26.0 21.1 17.3 14.5 12.3 10.7 s 9.2 8.0 7.2 6.3 5.7 5.0
• 8 5/8" ---- 85.2 65.2 51.5 41.7 34.3 28.8 24.7 21.2 18.5 16.2 14.3 12.7 11.3 10.3
GROUP IC:(ASTM F1043)Steel Pipe(50,000 psi yield)
• 1 5/8" 5.3 3.8 2.8 1.7 1.1
1 7/8" 7.6 5.6 4.2 2.6 1.7 1.1
2 3/8" 13.4 9.8 7.4 4.7 3.2 2.2 1.6 1.2
2 7/8" 24.2 17.7 13.5 8.6 5.9 4.3 3.2 2.4 1.9 1.5 1.2 ----
3 1/2" 37.0 27.1 20.7 13.2 9.1 6.6 5.0 3.9 3.1 2.5 2.0 1.7 1.4 1.1 ---
4" 49.2 36.1 27.6 17.6 12.2 8.9 6.8 5.3 4.2 3.4 2.8 2.4 2.0 1.7 1.4 1.2 1.0 ----
GROUP II: (ASTM F1043)High Strength Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x.105 5.7 4.2 3.1 2.0 1.3 ---
1 7/8"x 1 5/8"x.121 9.7 7.1 5.4 3.3 2.2 1.6 1.1 ----
2 1/4"x 1 5/8"x.121 11.2 8.2 6.2 3.9 2.6 1.8 1.3 ---
3 1/4"x 2 1/2"x .130 27.6 20.1 15.3 9.5 6.4 4.4 3.1 2.2 1.6 1.1 ----
See Table 12 for post dimensions and material properties.
(11)
•
TABLE 3
LINE POST SELECTION: WIND SPEED 120 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING,S(FEET)FOR USE IN EQUATION:S'=S X Cfl x Cf2 x Cf3
FENCE HEIGHT(FEET)
1. LINE POST ; 313.5
3.5 415161718 { 9 ; 10 1 11 1 12 13 1 14 1 15 1 16 ! 17 18 19 120 ;
SIZE IN I I i 1 i
Group IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 4.5 3.3 2.5 1.5 1.0
2 3/8" 7.8 5.7 4.4 2.8 1.9 1.3
2 7/8" 14.9 10.9 8.3 5.3 3.6 2.6 2.0 1.5 1.2
3 1/2" 24.2 17.7 13.6 8.7 6.0 4.4 3.3 2.6 2.1 1.7 1.4 1.1 ---
4" 33.6 24.7 18.9 12.1 8.4 6.1 4.7 3.6 2.9 2.4 2.0 1.7 1.4 1.2 1.0 ---
6 5/8" ---- ---- ---- 43.1 29.9 21.9 16.8 13.2 10.7 8.8 7.4 6.3 5.4 4.7 4.1 3.6 3.2 2.9 2.6
8 5/8" ---- 43.4 33.2 26.2 21.2 17.5 14.7 12.5 10.8 9.4 8.2 7.3 6.5 5.8 5.2
GROUP IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield strength)
1 7/8" 7.5 I 5.5 4.2 2.5 1.7 ---
2 3/8" 13.0 9.5 7.3 4.7 3.2 2.2
2 7/8" 24.8 18.2 13.8 8.8 6.0 4.3 3.3 2.5 2.0
3 1/2" 40.3 29.5 22.7 14.5 10.0 7.3 5.5 4.3 3.5 2.8 2.3 1.8 ----
4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ----
6 5/8" 71.8 49.8 36.5 28.0 22.0 17.8 14.7 12.3 10.5 9.0 7.8 6.8 6.0 5.3 4.8 4.3
•
8 5/8" ---- 72.3 55.3 43.7 35.3 29.2 24.5 20.8 18.0 15.7 13.7 12.2 10.8 9.7 8.7
GROUP IC:(ASTM F1043)Steel Pipe(50,000 psi yield)
" 1 5/8" 4.5 3.2 2.4 1.4
1 7/8" 6.5 4.7 3.6 2.2 1.4
2 3/8" 11.4 8.3 6.3 4.0 2.7 1.9 1.4 1.0
2 7/8" 20.5 15.1 11.5 7.3 5.0 3.6 2.7 2.1 1.6 1.3 1.0 ----
3 1/2" 31.4 23.1 17.6 11.2 7.8 5.6 4.3 3.3 2.6 2.1 1.7 1.4 1.2
4" 41.8 30.7 23.5 15.0 10.4 7.6 5.7 4.5 3.6 2.9 2.4 2.0 1.7 1.4 1.2 1.0
GROUP II: (ASTM F1043)High Strength Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x.105 4.8 3.5 2.7 1.7 1.1 ---
1 7/8"x 1 5/8"x.121 8.2 6.0 4.6 2.8 1.9 1.3 ---
2 1/4"x 1 5/8"x.121 9.5 6.9 5.3 3.3 2.2 1.5 1.1 ----
3 1/4"x 2 1/2"x.130 23.4 17.1 13 8.1 5.4 3.8 2.7 1.9 1.3 ---
See Table 12 for post dimensions and material properties.
(12)
TABLE 4
LINE POST SELECTION: WIND SPEED 130 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING,S(FEET)FOR USE IN EQUATION:S'=S X Cfl x Cf2 x Cf3
FENCE HEIGHT(FEET)
. LINE POST , 3 s3.5 s 4 I 5 I 6 7 1 8 9 10 11 1 12 j 13 14 1 15 16 I 17 1 18 ' 19 20
SIZE IN i I 3 1 I i s I
Group IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 3.8 2.8 2.1 1.3
2 3/8" 6.7 4.9 3.7 2.3 1.6 1.1
2 7/8" 12.6 9.3 7.1 4.5 3.1 2.2 1.7 1.3 1.0 ---
3 1/2" 20.6 15.1 11.5 7.4 5.1 3.7 2.8 2.2 1.8 1.4 1.2 ----
4" 28.6 21 16.1 10.3 7.1 5.2 4.0 3.1 2.5 2.0 1.7 1.4 1.2 1.0 ---
6 5/8" ---- ---- ---- 36.6 25.4 18.7 14.3 11.3 9.1 7.5 6.3 5.4 4.6 4.0 3.5 3.1 2.7 2.4 2.2
8 5/8" ---- 36.9 28.3 22.3 18.1 14.9 12.5 10.7 9.2 8.0 7.0 6.2 5.5 4.9 4.4
GROUP IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield strength)
1 7/8" 6.3 4.7 3.5 2.2
2 3/8" 11.2 8.2 6.2 3.8 2.7 1.8
2 7/8" 21.0 15.5 11.8 7.5 5.2 3.7 2.8 2.2 1.7
3 1/2" 34.3 25.2 19.2 12.3 8.5 6.2 4.7 3.7 3.0 2.3 2.0 ----
4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ----
6 5/8" ---- ---- ---- 61.0 42.3 31.2 23.8 18.8 15.2 12.5 10.5 9.0 7.7 6.7 5.8 5.2 4.5 4.0 3.7
8 5/8" ---- 61.5 47.2 37.2 30.2 24.8 20.8 17.8 15.3 13.3 11.7 10.3 9.2 8.2 7.3
GROUP IC:(ASTM F1043)Steel Pipe(50,000 psi yield)
1 5/8" 3.8 2.8 2.1 1.2
1 7/8" 5.5 4.0 3.0 1.9 1.2
2 3/8" 9.7 7.1 5.4 3.4 2.3 1.6 1.2
2 7/8" 17.5 12.8 9.8 6.2 4.3 3.1 2.3 1.8 1.4 1.1
3 1/2" 26.7 19.6 15.0 9.6 6.6 4.8 3.6 2.8 2.2 1.8 1.5 1.2 ---
4" 35.5 26.1 19.9 12.7 8.8 6.4 4.9 3.8 3.1 2.5 2.0 1.7 1.4 1.2 1.0 ---
GROUP II:(ASTM F1043)High Strength Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x.121 7.0 5.1 3.9 2.4 1.6 1.1 ---
2 1/4"x 1 5/8"x.121 8.1 5.9 4.5 2.8 1.9 1.3 ---
3 1/4"x 2 1/2"x.130 19.9 14.5 11.0 6.9 4.6 3.2 2.3 1.6 1.1 ---
See Table 12 for post dimensions and material properties.
(13)
TABLE 5
LINE POST SELECTION: WIND SPEED 140 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING, S (FEET) FOR USE IN EQUATION: S'=S X Cfl x Cf2 x Cf3
FENCE HEIGHT(FEET)
LINE POST3 { 3.5 ; 4 5 6 7 ; 8 € 9 10 I 11 1 12 I 13 I 14 I 15 16 17 i 18 19 20
SIZE IN I f
Group IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade (30,000 psi yield)
1 7/8" 3.3 2.4 1.8 1.1
2 3/8" 5.7 4.1 3.2 2.0 1.4
2 7/8" 10.8 7.9 6.0 3.8 2.6 1.9 1.4 1.1 ---
3 1/2" 17.5 12.8 9.8 6.3 4.3 3.2 2.4 1.9 1.5 1.2 ----
4" 24.3 17.8 13.6 8.7 6.0 4.4 3.4 2.6 2.1 1.7 1.4 1.2 1.0 ---
6 5/8" ---- ---- 31.1 21.6 15.9 12.1 9.6 7.7 6.4 5.4 4.5 3.9 3.4 3.0 2.6 2.3 2.1 1.9
8 5/8" - ---- 31.4 24.0 19.0 15.4 12.7 10.6 9.1 7.8 6.8 6.0 5.3 4.7 4.2 3.8
GROUP IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade (50,000 psi yield strength)
1 7/8" 5.5 4.0 3.0 1.8
2 3/8" 9.5 6.8 5.3 3.3 2.3
2 7/8" 18.0 13.2 10 6.3 4.3 3.2 2.3 1.8 ---
3 1/2" 29.2 21.3 16.3 10.5 7.2 5.3 4.0 3.2 2.5 2.0 ---
4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ----
6 5/8" ---- ---- ---- 51.8 36.0 26.5 20.2 16.0 12.8 10.7 9.0 7.5 6.5 5.7 5.0 4.3 3.8 3.5 3.2
8 5/8" ---- 52.3 40.0 31.7 25.7 21.2 17.7 15.2 13.0 11.3 10.0 8.8 7.8 7.0 6.3
GROUP IC: (ASTM F1043)Steel Pipe (50,000 psi yield)
' 1 5/8" 3.2 2.3 1.7 1.0
1 7/8" 4.7 3.4 2.6 1.6 1.0
2 3/8" 8.2 6.0 4.6 2.9 1.9 1.4
2 7/8" 14.8 10.9 8.3 5.3 3.6 2.6 2.0 1.5 1.2 ----
3 1/2" 22.7 16.7 12.7 8.1 5.6 4.1 3.1 2.4 1.9 1.5 1.2 1.0
4" 30.2 22.2 17.0 10.8 7.5 5.5 4.1 3.2 2.6 2.1 1.7 1.4 1.2 1.0 ---
GROUP II: (ASTM F1043)High Strength Cold Rolled Formed C-Shape (50,000 psi yield)
1 7/8"x 1 5/8"x.121 5.9 4.3 3.3 2.1 1.4 ---
2 1/4"x 1 5/8"x.121 6.9 5.0 3.8 2.4 1.6 1.1 ----
3 1/4"x 2 1/2"x.130 16.9 12.4 9.4 5.9 3.9 2.7 1.9 1.4 ---
See Table 12 for post dimensions and material properties.
(14)
TABLE 6
LINE POST SELECTION: WIND SPEED 150 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING, S (FEET) FOR USE IN EQUATION: S'=S X Cr' x Cf2 x Cf3
FENCE HEIGHT(FEET)
LINE POST 3 3.5 4 5 6 1 7 t 8 l 9 10 11 12 13 14 15 16 17 18 19 20
SIZE IN Group IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 2.8 2.0 1.5
2 3/8"
2 7/8" 9.1 6.7 5.1 3.3 2.2 1.6 1.2
3 1/2" 14.8 10.9 8.3 5.3 3.7 2.7 2.0 1.6 1.3 1.0 ---
4" 20.6 15.2 11.6 7.4 5.1 3.8 2.9 2.2 1.8 1.5 1.2 1.0 ----
6 5/8" ---- ---- ---- 26.4 18.4 13.5 10.3 8.1 6.6 5.4 4.6 3.9 3.3 2.9 2.5 2.2 2.0 1.8 1.6
8 5/8" ---- 26.7 20.4 16.1 13.0 10.8 9.0 7.7 6.6 5.8 5.1 4.5 4.0 3.6 3.2
GROUP IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade (50,000 psi yield strength)
1 7/8" 4.7 3.3 2.5
2 3/8" 8.0 5.8 4.5 2.8 1.8
2 7/8" 15.2 11.2 8.5 5.5 3.7 2.7 2.0
3 1/2" 24.7 18.2 13.8 8.8 6.2 4.5 3.3 2.7 2.2 1.7 ----
4"
--4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ---- -- - - --
6 5/8" ---- ---- ---- 44.0 30.7 22.5 17.2 13.5 11.0 9.0 7.7 6.5 5.5 4.8 4.2 3.7 3.3 3.0 2.7
8 5/8" - -- ---- 44.5 34.0 26.8 21.7 18.0 15.0 12.8 11.0 9.7 8.5 7.5 6.7 6.0 5.3
GROUP IC: (ASTM F1043)Steel Pipe (50,000 psi yield)
-- 1 5/8" 2.8 2.0 1.5
1 7/8"
2 3/8"
2 7/8" 12.6 9.2 7.1 4.5 3.1 2.2 1.7 1.3 ----
3 1/2" 19.3 14.2 10.8 6.9 4.8 3.5 2.6 2.0 1.6 1.3 1.1 ---
4" 25.7 18.8 14.4 9.2 6.4 4.6 3.5 2.8 2.2 1.8 1.5 1.2 1.0 ----
GROUP II: (ASTM F1043) High Strength Cold Rolled Formed C-Shape (50,000 psi yield)
1 7/8"x 1 5/8"x.105 3.0 2.2 1.6 1.0 ---
1 7/8"x 1 5/8"x.121 5.1 3.7 2.8 1.7 1.2 ---
2 1/4"x 1 5/8"x.121 5.8 4.3 3.2 2.0 1.3
3 1/4"x 2 1/2"x.130 14.4 10.5 8.0 5.0 3.3 2.3 1.6 1.2 ---
E
See Table 12 for post dimensions and material properties.
(15)
TABLE 7
LINE POST SELECTION: WIND SPEED 160 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING,S(FEET)FOR USE IN EQUATION:S'=S X Cf1 x Cf2 x Cf3
FENCE HEIGHT(FEET)
LINE POST 3 3.5 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
SIZE IN
Group IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 2.4 1.7 1.3
2 3/8" 4.1 3.0 2.3 1.4
2 7/8" 7.8 5.7 4.4 2.8 1.9 1.4 1.0
3 1/2" 12.6 9.3 7.1 4.5 3.1 2.3 1.7 1.3 1.1 ---
4" 17.6 12.9 9.9 6.3 4.4 3.2 2.4 1.9 1.5 1.2 1.0 ---
6 5/8" ---- ---- ---- 22.5 15.6 11.5 8.8 6.9 5.6 4.6 3.9 3.3 2.8 2.5 2.1 1.9 1.7 1.5 1.3
8 5/8" ---- 22.7 17.3 13.7 11.1 9.2 7.7 6.5 5.6 4.9 4.3 3.8 3.4 3.0 2.7
GROUP IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield strength)
1 7/8" 4.0 2.8 2.2
2 3/8" 6.8 5.0 3.8 2.3
2 7/8" 13.0 9.5 7.3 4.7 3.2 2.3 1.7
3 1/2" 21.0 15.5 11.8 7.5 5.2 3.8 2.8 2.2 1.8 ---
4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
6 5/8" ---- ---- ---- 37.5 26.0 19.2 14.7 11.5 9.3 7.7 6.5 5.5 4.7 4.2 3.5 3.2 2.8 2.5 2.2
8 5/8" ---- 37.8 28.8 22.8 18.5 15.3 12.8 10.8 9.3 8.2 7.2 6.3 5.7 5.0 4.5
GROUP IC: (ASTM F1043)Steel Pipe(50,000 psi yield)
1 5/8" 2.3 1.7 1.3
1 7/8" 3.4 2.5 1.9 1.1
2 3/8" 5.9 4.3 3.3 2.1 1.4 -
2 7/8" 10.7 7.9 6.0 3.8 2.6 1.9 1.4 1.1 ----
3 1/2" 16.4 12.0 9.2 5.9 4.0 2.9 2.2 1.7 1.4 1.1 ---
4" 21.8 16.0 12.2 7.8 5.4 3.9 3.0 2.3 1.9 1.5 1.3 1.0 ---
GROUP II:(ASTM F1043)High Strength Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x .121 4.3 3.1 2.4 1.5 --- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
2
3 1/4"x 2 1/2"x.130 12.2 8.9 6.8 4.2 2.8 2.0 1.4 ---
See Table 12 for post dimensions and material properties
(16)
•
TABLE 8
LINE POST SELECTION: WIND SPEED 170 MPH
EXPOSURE CATEGORY "B" (N/A = Not Available)
LINE POST MAXIMUM SPACING,S(FEET)FOR USE IN EQUATION: S'=S X Cf1 x Cf2 x Cf3
FENCE HEIGHT(FEET)
LINE POST 3 3.5 4 ' 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
SIZE IN I I 1 (
Group IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 2.0 1.5 1.1
2 3/8"
2 7/8" 6.6 4.8 3.7 2.4 1.6 1.2
3 1/2"
4" 14.9 11.0 8.4 5.4 3.7 2.7 2.1 1.6 1.3 1.1 ----
6 5/8" ---- ---- ---- 19.7 13.3 9.7 7.4 5.9 4.8 3.9 3.3 2.8 2.4 2.1 1.8 1.6 1.4 1.3 1.1
8 5/8" - ---- 19.3 14.7 11.6 9.4 7.8 6.5 5.6 4.8 4.2 3.7 3.2 2.9 2.6 2.3
GROUP IA: (ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield strength)
17/8"
2 3/8" 5.8 4.2 3.2 2.0 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- --- ---
2 7/8" 11.0 8.0 6.2 4.0 2.7 2.0
3 1/2" 17.8 13.2 10..0 6.3 4.5 3.2 2.5 1.8 ----
4" N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A ----
6 5/8" ---- ---- ---- 31.8 22.2 16.2 12.3 9.8 8.0 6.5 5.5 4.7 4.0 3.5 3.0 2.7 2.3 2.2 1.8
8 5/8" ---- 32.2 24.5 19.3 15.7 13.0 10.8 9.3 8.0 7.0 6.2 5.3 4.8 4.3 3.8
GROUP IC:(ASTM F1043)Steel Pipe(50,000 psi yield)
1 5/8" --
1 7/8"
2 3/8"
2 7/8"
3 1/2" 13.9 10.2 7.8 5.0 3.4 2.5 1.9 1.5 1.2 ----
4" 18.5 13.6 10.4 6.6 4.6 3.4 2.5 2.0 1.6 1.3 1.1 ----
GROUP II: (ASTM F1043)High Strength Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x.105 2.1 1.6 1.2 ---- --- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- I ----
1
2
3 1/4"x 2 1/2"x.130 10.4 7.6 5.8 3.6 2.4 1.7 1.2 ---- --- ---
See Table 12 for post dimensions and material properties.
(17)
TABLE 9
Mesh and Fabric Size Coefficients (Cfi)*
WIRE SIZE
FABRI
ZEI(O.D.) 3/8" 1/2 5/8" 1" 1 1/4' 1 3/4" 2" 2 '/4"
metric equiv.(mm)_> 9.5 12.7 15.8 25.4 31.8 44.5 50.8 57.1
diam. (in) diam.(mm)
.#5(0.207) 5.26 2.92 3.52 4.73 5.33 5.92
#6(0.192) 4.88 3.30 3.75 5.06 5.71 6.37
#8(0.162) 4.11 3.58 4.36 5.89 6.67 7.44
#9(0.148) 3.76 1.77 2.20 2.60 3.87 4.73 6.40 7.26 8.09
10(0.135) 3.43 1.88 2.36 2.80 4.19 5.13 6.96 7.90 8.82
11 (0.120) 3.0 2.06 2.60 3.10 4.65 5.71 7.77 8.83 9.86
12(0.113) 2.87 2.16 2.72 3.25 4.91 6.04 8.22 9.35 10.44
* - (Cf1) =1 for solid panel fence
(18)
TABLE 10
WIND EXPOSURE CATEGORY COEFFICIENTS (Cf2)
EXPOSURE Kz WIND COEFFICIENT: ( Kz EXP B ) / ( Kz )
CATEGORY
Fence 0-15 FT 15-20 FT 0-15 FT 15-20 FT
height
B 0.57 0.62 1.00 1.00
C 0.85 0.9 0.67 0.69
D 1.03 1.08 0.55 0.57
NOTES:
EXPOSURE B: Urban and suburban areas, wooded areas or other terrain with numerous closely
spaced obstructions having the size of single-family dwellings or larger.
•
EXPOSURE C: Open terrain with scattered obstructions having heights generally less than 30 ft.
This includes flat open country, grasslands, and all water surfaces in hurricane
prone regions.
EXPOSURE D: Flat, unobstructed areas and water surfaces outside hurricane-prone regions. This
category includes smooth mud flats, salt flats, and unbroken ice.
(19)
TABLE 11
Ice Exposure Coefficients (Cf3)
Regional Conditions Cf3
Regions likely to experience heavy ice storms 0.45
Regions subject to moderate icing effects 0.85
Regions not subject to the effects of icing 1.00
NOTES
1. Maximum spacing of posts may be limited by top rail design.
2. Recommended maximum spacing of posts not to exceed 10'-0".
3. For solid fence use exposure coefficient (Cf3) = 1.0.
4. Ice exposure coefficient is an arbitrary value that may be assigned based on the judgment of
the designer, considering the probability of an event occurring where maximum ice
accumulation and peak wind velocity occurs at the same time in the locality the fence is
installed.
(20)
TABLE 12
Line Post Material Properties Table (N/A = Not Available)
rTrade Size O.D. 1 I.D. I Sx lx Fy Mallow Em
O.D. 1 in. 1 in. 1 in.' 1 in° 1 lo /in' 1 lop-ft. 1 kipiini
Group IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 Regular Grade(30,000 psi yield)
1 7/8" 1.900 1.610 0.33 0.31 30 0.54 29000
2 318" 2.375 2.067 0.56 067 30 0.93 29000
2 7/8" 2.875 2.469 1.06 1.53 30 1.76 29000
3 1/2" 3.500 3.068 1.72 3.02 30 2.84 29000
4" 4.000 3.548 2.39 4.79 30 3.95 29000
6 518" 6.625 6.065 8.50 28.14 30 14.02 29000
8 5/8" 8.625 7.981 16.81 72.49 30 27.74 29000
Group IA:(ASTM F1043)Schedule 40 Steel Pipe,ASTM F1083 High Strength Grade(50,000 psi yield)
1 7/8" 1.900 1.610 0.33 0.31 50 0.90 29000
2 3/8" 2.375 2.067 0.56 0.67 50 1.54 29000
2 7/8" 2.875 2.469 1.06 1.53 50 2.93 29000
3 1/2" 3.500 3.068 1.72 3.02 50 4.74 29000
4" N/A N/A N/A N/A N/A N/A N/A
6 5/8" 6.625 6.065 8.50 28.14 50 23.38 29000
8 5/8" 8.625 7.981 16.81 72.49 50 46.23 29000
Group IC: (ASTM F1043)High Carbon Steel Pipe(50,000 psi yield)
1 5/8" 1.660 1.438 0.20 0.15 50 0.54 29000
1 7/8" 1.900 1.660 0.28 0.27 50 0.77 29000
2 3/8" 2.375 2.115 0.49 0.58 50 1.34 29000
2 7/8" 2.875 2.555 0.88 1.26 50 2.41 29000
3 1/2" 3.500 3.180 1.34 2.35 50 3.69 29000
4" 4.000 3.680 1.78 3.56 50 4.90 29000
Group II: (ASTM F1043) Cold Rolled Formed C-Shape(50,000 psi yield)
1 7/8"x 1 5/8"x 0.105" 0.23 0.33 50 0.63 29000
1 7/8"x 1 5/8"x 0.121" 0.39 0.36 50 1.07 29000
2 1/4"x 1 5/8"x 0.121" 0.45 0.52 50 1.24 29000
3 1/4"x 2 112"x 0.130" 1.11 1.88 50 3.05 29000
Sx Section Modulus lx Moment of Inertia Fx Minimum Yield
Mallow Allowable Moment Capacity Post (Fy)(Sx)0.66/12 in.ft
Em Modulus of Elasticity of Material
(21)
TABLE 13
Design Wind Pressure, q (LB / SF)
EXPOSURE Height Wind Velocity (MPH)
CATEGORY (ft) Kz
105 110 120 130 140 150 160 170
o- 15 0.57 16.00 16.58 19.74 23.16 26.86 30.84 35.09 39.61
B
15-20 0.62 16.44 18.04 21.47 25.19 29.22 33.54 38.16 43.08
0- 15 0.85 22.53 24.73 29.43 34.54 40.06 45.99 52.32 59.07
C
15-20 0.90 23.86 26.18 31.16 36.57 42.42 48.69 55.40 62.54
0- 15 1.03 27.30 29.97 35.66 41.85 48.54 55.72 63.40 71.57
D
15-20 1.08 28.63 31.42 37.39 43.89 50.90 58.43 66.48 75.05
NOTES:
q = (0.00256)(Kz)(Kzt)(Kd)G)(Cf)(V2)
Kz= EXPOSURE COEFFICIENT(GIVEN ABOVE)
Kzt= 1.0 (TOPOGRAPHIC FACTOR, PRESUMED = 1 FOR NO TOPOGRAPHIC EFFECTS)
Kd = 0.85 (DIRECTIONALITY FACTOR)
G = .85 (GUST FACTOR)
Cf= 1.3 (FORCE COEFFICIENT)
V=VELOCITY (GIVEN ABOVE)
REF: ASCE 7-10, "MINIMUM DESIGN LOADS FOR BUILDINGS AND OTHER STRUCTURES"
(22)
CHAPTER 26 WIND LOADS: GENERAL REQUIREMENTS
•
^ir
1OQ(4t) l `,
N
.. 105(47)
z
LT
140'63) 130(58)
120(54)
110149)
105(47} .=
•
105(47)
110(49)
N 120(54)
130(58)
140(63)
150(67
150(67)
Figure 26.5-1C Basic Wind Speeds for Occupancy Category I Buildings and Other Structures.
Notes:
1. Values are nominal design 3-second gust wind speeds in miles per hour(m/s) at 33 ft(l Om) above ground for
Exposure C category.
2. Linear interpolation between contours is permitted.
3. Islands and coastal areas outside the last contour shall use the last wind speed contour of the coastal area.
4. Mountainous terrain,gorges,ocean promontories, and special wind regions shall be examined for unusual wind
conditions.
5. Wind speeds correspond to approximately a 15%probability of exceedance in 50 years(Annual Exceedance
Probability =0.00333,MRI=300 Years).
249a (23)
. .
MINIMUM DEIGN LOADS
105(47)
110(49)
120(54)
I:.. ..-<t ,` 130(58)
. 7140(63)
-,- • :,,.„,... '7',..„._': :t. ..tt.. t„'',...t.-; "„7„.:
1 -,;;
[:,---r-''::::--,).-f:ç <4
-e-- ,--- 44.,.„ ,_.
. ..,:,,..,..;-,17.1,..:', ,:;1,.....-1:tZtSft."-,.„,„,,..r.A. , ST, ,, •,.),
, ,,,,,.., N 1.,„H ,^r7 .., =--,-,.,k•-••-#-,1„,-1-,---,-- •_, . • - ,• ---•••
--,--;•••-•2 ,------7.7.-\:_t„--`, ?--11--"--J----[•-1--till ,•••Lii-•-•:-,r ri.,••'1,44-7.•,,,-,i,:•;',r,-•;„1-:'-- -g •'''':•,f..• '-ip '••,•-•
• - ' ' •-'----r4-•••'-•f---1-„_,Tt,•-•.-----_-cf.:.1.--':-..*-c").-",-,--- ", , ,,-1,--c,--t1,..,-"•---tttlk- • f ‘• 4z, •
..,,...•.,::::"..,• -.1-,•,.•-•,,,lij-t...,-•••,.,2,,-,,t,,,,.;-",:_ril--•,•-•,•-:').-,",La-•••:• •_}.",••,--,-- p---t-.1-cp•- - ,-,,,,i•<1,. ,... ' --,-.
;"---,'"_--':---7,_-'17-ri-±7-7.:•-••-koi-c•-"4-•,.-\--14-•,.-'":_?s,Tql.,- 0:1- e,'•_,.._...,....„,'-r, . ..-•,•••••:1.),.."-_-•_i'L - `•"--'-"---':.'
4-''''''-f-'-'1--t-itlpeUrTr'--t4'''''IY•tii'''S,17•P 40:01140416. ,'s '. Al,.."'','",t'..- 140(63)
---+-1- - ..- ----' t-),Ic 7--)tr"1-' ts-sk- -t•40 arlpfr. -- _.'",,,,--,- „
--,,',.„,)--„..;..„,,,„„„4.7.-.1- --t-1,4---)--1-_,,A., ,` -1....;:kt.,,,,,- .'• .....- .11,40,t4 i* .,,,r-, ,...):. .
4041.411‘ t.- --
-,"'
4----ti"-'4"ri.4"--4
i''''.., 130(58)
140(63)
- 7 ,. •
; j 160(72)
150(67)
,,..
170(76)
..,__.../—
105(47)
"...
140(63) 170(76)
110(49)
120(54) 30(58)
(mis) 140(63) 150(676)0,72.
(80) - t--- -,11 "
Location Special Wind Region
Location
180
Guam
150 (67)
Virgin Islands
150 (67) Puerto Rico
American Samp? , ., r,.....„: .:,?c•IT;;I:1:1 115 (51)
Hawaii—,f.,..)1)7. :t;..a'.J.I.,„,...111,..,4):... .44.... , .,
Figure 26.5-1 e (Continued)
249b
(24)
APPENDIX
METRIC CONVERSION FACTORS
LENGTH:
1Ft = 0.304 8 m
lIn = 25.4mm
AREA:
1 sq ft = 0.0929 sq m
1 sq in = 645.16 sq mm
VELOCITY, SPEED:
1 Mph = 1.6093 km/h
MASS:
1 lb = 0.4536 kg
MASS PER UNIT AREA:
1 lblsq ft = 4.88224 kg/sq m
FORCE:
1 kip(1,000 lbf)= 4.44822 kN
1 lbf(pound-force)= 4.44822 N
FORCE PER UNIT LENGTH:
1 lb/ft = 14.5939 N/m
1 lb/in = 175.1268 N
PRESSURE. STRESS. MODULUS OF ELAST1CIlY (FORCE/UNIT AREA):
1 lb/sq in = 6.8947 kPa
1 lb/sq ft = 47.8803 Pa
(25)
CHAPTER 26 WIND LOADS: GENERAL REQUIREMENTS
Terrain E=pos re Constants I
Table 26.9-1
Exposure a z (ft) A A� e zm;0(ft)*
a
K 7.0 1200 1/7 0.84 1/4.0 0.45 0.30 320 1/3.0 30
C 9.5 900 1/9.5 1.00 1/6.5 0.65 0.20 500 1/5.0 15
D II.5 700 1/11.5 1.07 1/9.0 0.80 0.15 650 1/8.0 7
=minimum height used to ensure that the equivalent height Z is greater of 0.64 or
For buildings with h 5 z.„„F Z shall be taken as ate,,.
In metric
Exposure a. z (m) Aa A
a b C !on) z,,,in(m)
K 7.0 365.76 1/7 0.84 1/4.0 0.45 0.30 97.54 1/3.0 9.14
C 9.5 274.32 1/9.5 1.00 1/6.5 0.65 0.20 152.4 1/5.0 4.57
D 11.5 213.36 1/11.5 1.07 1/9.0 0.80 0.15 198.12 1/8.0 2.13
*z _minimum height used to ensure that the equivalent height Z is greater of 0.6h orz�.
For butfdttga with h 5 z,.,, Z shall be taken as
• 256 (26)
•
26.7.3 Exposure Categories
Exposure B:For buildings with a mean roof height of less than or equal to 30 ft(9.1 m),Exposure
B shall apply where the ground surface roughness,as defined by Surface Roughness B,prevails in the
upwind direction for a distance greater than 1,500 ft(457 m). For buildings with a mean roof height
greater than 30 ft(9.1 m),Exposure B shall apply where Surface Roughness B prevails in the upwind
direction for a distance greater than 2,600 ft(792 m)or 20 times the height of the building,whichever
is greater.
Exposure C:Exposure C shall apply for all cases where Exposures B or D do not apply.
Exposure D:Exposure D shall apply where the ground surface roughness,as defined by Surface
Roughness D,prevails in the upwind direction for a distance greater than 5,000 ft(1,524 m)or 20 times
the building height,whichever is greater.Exposure D shall also apply where the ground surface
roughness immediately upwind of the site is B or C,and the site is within a distance of 600 ft(183 m)
or 20 times the building height,whichever is greater,from an Exposure D condition as defined in the
previous sentence.For a site located in the transition zone between exposure categories,the category
resulting in the largest wind forces shall be used.
EXCEPTION: An intermediate exposure between the preceding categories is permitted in a transition
zone provided that it is determined by a rational analysis method defi ned in the recognized literature.
29.3.2 Velocity Pressure
Velocity pressure,qz,evaluated at height z shall be calculated by the
following equation:
qz=0.00256 KzKztKdV2(lb/ft2)(29.3-1)
[In SI:qz=0.613 KzKztKdV2(N/m2);V in m/s]
where:
Kd=wind directionality factor defined in Section 26.6
Kz=velocity pressure exposure coeffi cient defined in Section 29.3.1
Kzt=topographic factor defined in Section 26.8.2
V=basic wind speed from Section 26.5.
qh=velocity pressure calculated using Eq.29.3-1 at height h
The numerical coefficient 0.00256(0.613 in SI) shall be used except where sufficient climatic
data are available to justify the selection of a different value of this factor for a design application.
(27)
CHAPTER 26 WIND LOADS: GENERAL REQUIREMENTS
Wind Directionality Factor, Kd
Table 26.6-1
Structure Type Directionality Factor Kd*
Buildings
Main Wind Force Resisting System 0.85
Components and Cladding 0.85
Arched Roofs 0.85
Chimneys, Tanks,and Similar Structures
Square 0.90
Hexagonal 0.95
Round 0.95
Solid Freestanding Walls and Solid
Freestanding and Attached Signs 0.85
Open Signs and Lattice Framework 0.85
Trussed Towers
Triangular, square, rectangular 0.85
All other cross sections 0.95
*Directionality Factor Kd has been calibrated with combinations of loads
specified in Chapter 2. This factor shall only be applied when used in
conjunction with load combinations specified in Sections 2.3 and 2.4.
250 (28)
CHAPTER 29 WIND LOADS ON OTHER STRUCTURES AND BUILDING APPURTENANCES-MWFRS
Velocity Pressure Exposure Coefficients, Kh and KZ I
Table 29.3-1
Height above Exposure
' ground level,z
B C D
ft (m)
0-15 (0-4.6) 0.57 0.85 1.03
20 (6.1) 0.62 0.90 1.08
25 (7.6) 0.66 0.94 1.12
30 (9.1) 0.70 _ 0.98 1.16
40 (12.2) 0.76 1.04 1.22
50 (15.2) 0.81 1.09 1.27
60 (18) 0.85 1.13 1.31
70 (21.3) 0.89 1.17 1.34
80 (24.4) 0.93 1.21 1.38
90 (27.4) 0.96 1.24 1.40
100 (30.5) 0.99 1.26 1.43
120 (36.6) 1.04 1.31 1.48
140 (42.7) 1.09 1.36 1.52
160 (48.8) 1.13 1.39 1.55
180 (54.9) 1.17 1.43 1.58
200 (61.0) 1.20 1.46 1.61
250 (76.2) 1.28 1.53 1.68
300 (91.4) L35 1.59 1.73
350 (106.7) 1.41 1.64 1.78
400 (121.9) 1.47 1.69 1.82
450 (137.2) 1.52 1.73 1.86
500 (152.4) 1.56 1.77 1.89
Notes:
1. The velocity pressure exposure coefficient KZ may be determined from the following
formula:
For 15 ft. <z<zg For z< 15 ft.
Kz=2.01 (z/zg)2 Kz=2.01 (15/zg)2/a
2. a and zg are tabulated in Table 26.9.1.
3. Linear interpolation for intermediate values of height z is acceptable.
4. Exposure categories are defined in Section 26.7.
310 (29)
MINIMUM DESIGN LOADS
Design Wind Loads All Heights
Figure 29.4-1 ( Force Coefficients,Cf Solid Freestanding Walls
Other Structures & Solid Freestanding Signs
• kSOL nseNGR 1 _ ealan
F /� 14-"14-"/HIHI
h CASE A WIND F
F
W F
WIND
.",„,,,,,,,,o u�v`ncF,e.�.�.,�,.�,V CASE C
ELEVATION VIEWF s
aal-
w'� � 4-0 2E1141 - 1F= "*1<-2->1
Il• F
h_s�- srz i~
nlz I '-‘ii,,_F 4, ,..,s� F F F ND
WINDF
nn s t F
V I I t*
s/h c 1 GROUND sURcecc sln=1 WINO
o.2B 505w
CROSS-SECTION VIEW PLAN VIEWS
C,,CASE A&CASE B
Clearance Aspect Ratio,B/s
Ratio,s/h <0.05 0.1 0.2 0.5 1 2 4 5 10 20 30 45
1 1.80 1.70 1.65 1.55 1.45 1.40 1.35 1.35 1.30 1.30 1.30 1.30
0.9 1.85 1.75 1.70 1.60 1.55 1.50 1.45 1.45 1.40 1.40 1.40 1.40
0.7 1.90 1.85 1.75 1.70 1.65 1.60 1.60 1.55 1.55 1.55 1.55 1.55
0.5 1.95 1.85 1.80 1.75 1.75 1.70 1.70 1.70 1.70 1.70 1.70 1.75
0.3 1.95 1.90 1.85 1.80 1.80 1.80 1.80 1.80 1.80 1.85 1.85 1.85
0.2 1.95 1.90 1.85 1.80 1.80 1.80 1.80 1.80 1.85 1.90 1.90 1.95
0.16 1.95 1.90 1.85 1.85 1.80 1.80 1.85 1.85 1.85 1.90 1.90 1.95
Cr,CASE C
Region Region
(horizontal Aspect Ratio.B/s Ihon:mdxl Aspect Ratio,B/s
distance from distance from
windward edge) 2 3 4 5 _ 6 7 8 9 10 windward edge) 13 >45
0 to s 2.25 2.60 2.90 3.10" 3.30" 3.40" 3.55` 3.65* 3.75" 0 to s 4.00* 4.30*
"
s to 2s 1.50 1.70 1.90 2.00 2.15 2.25 2.30 2.35 2.45 sto 2s 2.60 2.55
2s to 3s1._15 1.30 1.45 1.55 1.65 1.70 1.75 1.85 2s to 3s 2.00 1.95
- 3s to 10s i ‘ = 1.10 1.05 1.05 1.05 1.05 1.00 0.95 3s to 4s 1.50 1.85
' 'Values shag De multipliedELAN VIEW OF WALL OR SIGN WITH 4s to 5s 1.35 1.85
lo/y Reductogifactur
by the following reductiont 0 0.75 L`$ I A RETURN CORNER 5s to 10s 0.90 1.10
`actor when a return
-z 0,60 7 k B >I >10s 0.55 0.55
Notes:
1.The term"signs"in notes below also applies to"freestanding walls".
2.Signs with openings comprising less than 30%of the gross area are classified as solid signs. Force coefficients for solid signs with openings
shall be permitted to be multiplied by the reduction factor(1-(1-01 5).
3 To allow for both normal and oblique wind directions,the following cases shall be considered:
For s/h<1:
CASE A: resultant force acts normal to the face of the sign through the geometric center.
CASE B: resultant force acts normal to the face of the sign at a distance from the geometric center
toward the windward edge equal to 0.2 times the average width of the sign.
For B/s>2,CASE C must also be considered:
CASE C: resultant forces act normal to the face of the sign through the geometric centers of each region.
For s/h=1:
The same cases as above except that the vertical locations of the resultant forces occur at a distance above
the geometric center equal to 0.05 times the average height of the sign.
4.For CASE C where s/h>0.8,force coefficients shall be multiplied by the reduction factor(1.8-s/h).
5. Linear interpolation is permitted for values of s/h,13/s and L,/s other than shown.
6.Notation:
B:horizontal dimension of sign,in feet(meters);
h:height of the sign,in feet(meters);
s:vertical dimension of the sign,in feet(meters);
0:ratio of solid area to gross area;
L,:horizontal dimension of return corner,in feet(meters)
(30)
CHAPTER 26 WIND LOADS: GENERAL REQUIREMENTS
Topographic Factor, Kzt
Figure 26.8-1
•
z z
•
PI
x(firdnif) x(Upwi.d) - x(Downwind)
•
\%
\'.
ESCARPMENT 2-D RIDGE OR 3-0 AXISYMMETRICAL HILL
Topographic Multipliers for Exposure C
K, Multiplier K2 Multiplier K3 Multiplier
H/Lh 2-D 2-D 3-D x/Lh 2-D All z/Lh 2-D 2-D 3-D
Ridge Escarp. Axisym. Escarp. Other Ridge Escarp. Axisym.
Hill Cases Hill
0.20 0.29 0.17 0.21 0.00 1.00 1.00 0.00 1.00 1.00 1.00
0.25 0.36 0.21 0.26 0.50 0.88 0.67 0.10 0.74 0.78 0.67
0.30 0.43 0.26 0.32 1.00 0.75 0.33 0.20 0.55 0.61 0.45
0.35 0.51 0.30 0.37 1.50 0.63 0.00 0.30 0.41 0.47 0.30
0.40 0.58 0.34 0.42 2.00 0.50 0.00 0.40 0.30 0.37 0.20
0.45 0.65 0.38 0.47 2.50 0.38 0.00 0.50 0.22 0.29 0.14
0.50 0.72 0.43 0.53 3.00 0.25 0.00 0.60 0.17 0.22 0.09
• 3.50 0.13 0.00 0.70 0.12 0.17 0.06
4.00 0.00 0.00 0.80 0.09 0.14 0.04
0.90 0.07 0.11 0.03
1.00 0.05 0.08 0.02
1.50 0.01 0.02 0.00
2.00 0.00 0.00 0.00
Notes:
1. For values of H/Lh,x/Lh and z/Lh other than those shown, linear interpolation is permitted.
2. For H/Lh>0.5,assume H/Lh=0.5 for evaluating Ki and substitute 2H for Lh for evaluating K2 and K3.
3. Multipliers are based on the assumption that wind approaches the hill or escarpment along the
direction of maximum slope.
4. Notation:
H: Height of hill or escarpment relative to the upwind terrain, in feet(meters).
Lh: Distance upwind of crest to where the difference in ground elevation is half the height of hill or
escarpment, in feet(meters).
K,: Factor to account for shape of topographic feature and maximum speed-up effect.
K2: Factor to account for reduction in speed-up with distance upwind or downwind of crest.
K3: Factor to account for reduction in speed-up with height above local terrain.
x: Distance (upwind or downwind) from the crest to the building site, in feet(meters).
z: Height above ground surface at building site, in feet(meters).
µ: Horizontal attenuation factor.
y: Height attenuation factor.
252 (31)