TIdEIA
”
STANDARD
ANSl/TIA/ElA-222-f-1QQ6
Approved: March 29, 1996
Structural
Standards for Steel Antenna
Towers and Antenna Supporting
Structures
.
TIAIFJA-222-F
(Revision of ELUTLbZZf-E)JUNE 1996
TELECOMMUNICATIONS
INDUSTRY ASSOCIATION
. .
i -- Reproduced By GLORAL = = ENGINEERING DOCUMENTS
m= WlthlhePetrniuion01EiA
ws Under Roy&y A~mement
June 10, 1996
TO: Recipients of new TIA Standards and Engineering Publications
Enclosed please find one copy of the following TINEIA Standard:
TINEIA-222-F Structural Standards for Steel Antenna Towers and Antenna Supporting Structures
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Sincerely,
Cecilia tie&g
Engineering Department
enclosure
Remmng me te/ecommufl/calk7flS u7au.w m
NOTICE
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This Standard does not purport to address all safety problems associated with its use or all applicable regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and kahh practices and to determine the applicability of reguIatory limitations before its use. (From Standards Proposal No. 3278, formulated under the cognizance of the TR-14.7 Structural Standards for Steel Antenna Towers and Antenna Supporting Structures Subcommittee
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Section
STRUCTURAL STANDARDS FOR STEEL ANTENNA TOWERS AND
ANTENNA SUPPORTING STRUCTURES CONTENTS Page Number
OBJEC’TWE . . .
SCOPE...
MATERIAL ... 1.1 Standard ... LOADING ... 2.1 Definitions ... ... 2.2 Nomenclature for Section 2 Loading ...2.3 Standard ... 2.4 References ... STRESSES ... 3.1 Standard ...
MANUFACTURE AND WORKMANSHIP ... 4.1 Standard...~ ... FACTORYFINISH ...
5.1 Standard ...
PLANS, ASSEMBLY TOLERANCE& AND MARKING ... 6.1 Standard ...
FOUNDATIONS AND ANCHORS ... 7.1 Definitions.. ...
7.2 Standard ... 7.3 Special Conditions ... 7.4 FoundationDrawings ... SAFE‘TY FACTOR OF GUYS ... 8.1 Defmition ...
8.2 Standard...~ ... PRESTRESSING AND PROOF LOADING OF GUYS ... 9.1 Definitions.. ... 9.2 Standard ... 1 1 1 1 2 2 3 4 11 11 11 18 18 18 18 18 18 19 19 19 i0 21 21 21 21 21 21 22 3 a 4 5 6 7 8 * ” 9
TIAEIA-222-F CONTENTS (Continued) Section
c
,
a
Page Number 10 INITIAL GUY TENSION , . . .11 12 13 14 15 16 10.1 Definition ... 10.2 Standard ... 10.3 Method Of Measurement ... OPERATIONAL REQ IJ-mMmTs ... 11.1 Definitions ... ...
11.2 Standard ...
PROTECTIVE GROUNDING ... 12.1 Definitions ...
12.2 Standard ...
~JMJXPG AND WOlSKING FACILITIES ... 13.1 Definitions ... ...
13.2 standard ...
-PWI’KE AND INSPECTION ... 14.1 Standard ...
~A.LxIS OF EXKI’ING TOWERS AND STRUCTURES ... 15.1 Standard...\ ... COUNTY LISTINGS OF MINMLJMBASIC WIND SPEEDS ...
ANNEXES
PU-KI-WER CHECKLIST ... Annex A:
Annex B: DESIGN WIND LOAD ON TYFICAL MICROWAVE
ANTENNAS/REFLECTORS . . . TABLE OF ALLOWABLE TWIST AND SWAY VALUES FOR
PARABOLIC ANTENNAS, PASSIVE REFLECTORS, AND
PERISCOPE SYSTEM REFLECTORS . . . DETERMINATION OF ALLOWABLE BEAM TWJST Am SWAY FOR CROSS-POLARIZATION LIMITED SYSTEMS . . . TOWER MAINTENANCE AND INSPECTION PROCEDURES . . . . CRITERIA FOR THE ANALYSIS OF EXISTING STRUCTURES . . . SI CONVERSION FACTORS . . . COwmY ON ICE DESIGN CRITERIA FOR
CO-CATION STRUCTURES.. . . . Annex C: Annex D: Annex E: Annex F: Annex G: Annex H: Annex I: Annex J: 22 22 22 22 22 22 22 23 23 23 23 23 23 24 24 24 24 25 59 61 71 77 83 101 103 105 GEOTECHNICAL JJqVESTIGAnONS FOR TOWERS . . . ,109 CORROSION CONTROL OPTIONS FOR GUY ANCHORS
STRUCTURAL STANDARDS FOR STEEL ANTENNA TOWERS AND ANTENNA SUPPORTING STRUCTURES
OBJECTIVE
The objective of these standards is to provide I&,&= uitezia for specifying and designing steel antenna towers and antenna supporting structures. These standards are not intended to replace or supersede applicable codes. me information contained in these standards was obtained from sources as referenced and noted herein and represents, in the judgement of the subcommittee, the accepted industry practices for minimum standards fa the design of steel antenna suppohg structures. It is for general information only. while it ia believed to be accurate, this information should not be relied upon for any specific application without competent professional examination and verification of its accuracy, suitability, and applicability by a licensed professional engineer These standards utilize wind loading criteria baaed on an annual probability and are not intended to
cover d environmental conditions which could exist at a particular location.
These standards apply to steel antenna towers and antenna supporting structures for all classes of cmmmications service, such as AM, CATS, FM, Microwave, Cellular, TV, VHF, etc.
These standards may be adapted for international use; however, it is necessary to determine the appropriate basic wind speed (fastest-mile) and ice load at the site location in the specific co~npy based on local meteorological data.
Equivalent International System of Units (SI) are given iu brackets [ ] throughout these standards. SI conversion factors have been provided in Annex G.
It is the responsibility of the purchaser to provide site-specific data and requirements differing from
those contained in these standards.
Annex A provides a checklist for assisting the purchaser i.n specifying the requirements for a specific structure when using these standards.. The user is cautioned that local conditions of wind and ice, if known, have precedence over the minimum standards described herein.
SCOPE
These standards describe the requirements for steel antenna towers and antenna supporting stnmures.
1 MAIERIAJd 1.1 Standard
1.1.1 Material shall conform to one of the following standards except as provided in 1.1.2. 1.1.1.1 Structural steel, cast steel, steel forgings, and bolts shall confom~ to the material
specifications listed in the June 1, 1989, American Institute of Steel Constmction, “Specification for Structural Steel Buildings - Allowable Stress Design and Plastic Design”, hereinafter referred to as the AISC specification.
1.1.1.2 Light gauge steel stmctural members shall be structural quality as defined by the August 19, 1986, American Iron and Steel Institute, “Specification for the Design of Cold-Formed Steel Stmctural Members”, hereinafter referred to as the AISI spe@fication.
1.1.1.3 Material for tubular steel pole structures and components shall conform to section 7.0 of A.NSI/NEhtA TTl- 1983, “Tapered Tubular Steel Structures”.
- -- - -1. l ----I
1.1.2 When materials other than hose specified herein are used, the supplier must Provide certified data concerning mechanical and chemical properties.
1-1-3 Bolts and nut locking devices (excluding guy hardware).
1.1.3.1 Sl.@xitical coM&o~ md ~nnections subjected to tension where the
application of externally applied load results in prying action produced by deformation of the connected parts sha.U be m& v&h b&h-strength bolts tightened to the miuimum bolt tensions specified in the November 13, 1985, AISC, “Specification for Structural Joints using ASTM A325 or A490 Bolts”.
EepbOn: where it can be shown that the stiffness of the connected parts is sufficient to rtth= prying forces to ittsignifrcauce, tension connections may be made with high-strength bolts tightened to a snug-tight condition as defined in the AISC specification refened to in 1.1.3.1.
(Note: Contact surfaces for slip-critical connections shall not be oiled or painted and for galvanized material, the contact surfaces shall be prepared in accordance with the DISC specification referred to in 1.1.3.1.)
1.1.3.2 Bearing-type connections may be made with high-strength bolts tightened to a snug-tight condition as defined in the AIsC specification referred to in 1.1.3.1.
1.1.3.3 Where high-strength bolts are used and tensioned in accordance with the mc specification referred to in 1.1.3.1, a nut-locking device is not required.
1.1.3.4 Bolts not covered in 1.1.3.3 require a nut-locking device. 1.1.3.5 Hot-dip galvan&& A490 bolts shall not be used.
1.1.4 Materials other than steel are not within the &ope of this section. 2 LOADING
2.1 Definitions
2.1.1 Dead Load - The weight of the structure, guys. and appurtenances.
2.1.2 Ice Load - The radial thickness of ice applied uniformly around the exposed surfaces of the structure, guys, and appurtenances.
2.1.2.1 solid ice.
Unless otherwise indicated, a specified radial ice thickness shall be considered as 2.1.2.2 The density of solid ice shall be considered to be 56 lb/f9 18.8 kN/m3].
2.1.2.3 The density of rime ice shall be considered to be 30 lb/@ [4.7 kN/m3]. 2.1.3 Wind Load - The wind loading requ&ments specified in 2.3 (see Annex A).
2.1.3.1 Basic Wind Speed - Fastest-de wind speed at 33 ft [lo m] above ground corresponding to an annual probability of 0.02 @O-year nmrrence interval).
2.1.4 Appurtenances - Items attached to the structure such as m*MaS, transmission lines,
conduits, lighting equipment, climbing devices, platforms, signs, anti-climbing devices, etc.
-
I)
2.1.4.1 Discrete Appurtenance - An appurtenance whose load can be assumed to be2.1.4.2 Linear Appurtenance - An appurtenance whose load can be assumed to be distributed over a section of the structure.
2.2 Nomenclature for Section 2 Loading
AA Projected area of a &near appurteuance AC Projected area of a &Crete appurtenance
42 Effective projected area of structural components in me face AF Projected area of fit structural componeuts in one face AC Gross area of one tower face as if the face were solid AR Projected area of round structural components in one face
C Velocity coefficient for tubular pole structure force coefficients
CA Linear or discrete appurtenance force coeffkient CD Guy hag force coeffkient
CF Structure force coefficient CL GUY lift force coefficient
D Dead weight of the structure, guys, and appurtenances Wind direction factor for flat structural components
Average diameter or average least width of a tubular pole stmctm Wind direction factor for round structural co&ponents
Horizontal force applied to a section of the structure Design wind load on a discrete appurtenance
Total drag force on a guy Total lift force on a guy
0
.?F
DP DR F FC FD FL @I I Kz Lc RR V WIGust response factor for fastest-mile basic wind speed Weight of ice
Exposure coefficient Chord length of guy
0
WOd e
Reduction factor for round structural components Basic wind speed for the structure location
Design wind load on the structure, appurte~ccs, @Ys, etc.9 with radial ice Design wind load on the structure, appurtenmccs, gUY% e% without ice Diameter of guy strand
h Total height of structure 92 Velocity pressure
r Ratio of comer diameter to diameter of inscribed circle of a tubular pole structure t Radii thickness of ice
Z Height above average ground level to midpoint of section, appurtenance or gUY
8 Clockwise angle from guy chord to wind direction vector 2.3 Standard
2.3.1 Wind and Ice Loads
2.3.1.1 The total design wind load shall include the sum of the horizontal forces applied to the structure in the direction of the wind and the design wind load on guys and discrete appurtenances.
231.2 This standard does not specifically state an ice requirement. Ice loading,
depending on tower height, elevation, and exposure, may be a significant load on the stnmure in most parts of the United States. If the structure is to be located where ice accumulation is expected, consideration shall be given to an ice load when specify& the requirements for the structure. (Refer to Annexes A and H.)
2.3.2 The horizontal force (F) applied to each section of the structure shall be calculated from the equation:
F=qzGHCCFAE+~(CAAP31(lb>N ; Not to exceed 2 QZ G &
where AC = Gross area of one tower face (ft2) [m2]
(Note: All appurtenances, including antennas, mounts and lines, shall be assumed to remain intact and attached to the stmcture regardless of their wind load capacities.)
2.3.3 The velocity pressure (Q) and the exposure coeffkient (K3;) shall be calculated from the equations (see Annex A):
Q = -00% Kz V2 (lb/ft2) for V in mi/h or
qz=.613KzV2PJforVinm/s Kz = M3312” for 2 in ft or Kz = Cx/1012n for 2 in meters
1.00 2 Kz < 2.58
V = Basic wid speed for the structure location (mi/h) Cm/s1
z = Height above average ground level to midpoint of the section (ft) [ml
2.3.3.1 Unless otherwise specified, the basic wind speed W) for the structure location shall be determined from section 16.
2.3.4 Gust Response Factors
2.3.4.1 For latticed structures, the gust response factor (GH) shall be calculated from the equation:
&I = .65 + .6O/(h/33)’ I7 for h in ft or %I = .65 + .60&h/10)’ I7 for h iu meters 1.00 2 G-JJ < 1.25
2.3.4.2 For tubular pole structures, the
gust
response factor (GH) shall be 1.69. 2.3.4.3 One gust response factor shall apply for the entire structure.2.344 When cantilevered tubular or latticed pole structures are mounted on latticed structures, the gust response factor for the pole and the latticed structure shall be based on the height of the latticed structure without the pole. The stresses calculated for pole structures and their connections to latticed structures shall be multiplied by 1.25 to compensate for the greater gust response for mounted pole structures.
23.5 Structure Force Coefficients
2.3.5.1 For latticed structures, the structure force coefficient (CF) for each section of the mct~e shai.i be calculated from the equations:
CF = 4.0e2 - 5.9e + 4.0 (Square cross sections) CF = 3.4e2 - 4.7e + 3.4 (Triangular cross sections) e = Sdidity Ratio = (AF + AR)/& :
AF = Projected area (ft2) [rnz] of flat structural components in one face of the section. AR = Projected area (ft2) [m2] of round structural components in one face of the section and the projected area of ice when specified on flat and round structural components. (Refer to Figure 1).
(Note: The projected area of structural components shall include the projected area of connection plates.)
I 1A1tl.b222-F
t
1Ly
I
/ \ \
\
0’
\
-2
t = Specified radial thickness of ice Figure 1
(Note: Ice, when specified, shall be assumed to accumulate uniformly on all surfaces as illustrated. The additional projected area caused by the ice accumulation may be considered cylindrical even though the bare projected area is flat. Consideration shall be given to the change in shape from round to flat for closely spaced linear appurtenances with ice accumulations.)
2.3.5.2 For cantilevered tubular steel pole structures, the structure force coefficient (CF) shall be determined from Table 1.
2.3.6 The effective projected area of structural components (AE) for a section shail be calculated from the equation:
AE = DF AF + DR AR RR (f$) Cm*]
(Note: For tubular steel pole structures, AE shall be the actual projected area based on pole diameter or overall width.)
2.3.6.1 The wind direction factors, & and &, shall be determined from Table 2.
2.3.6.2 The reduction factor (RR) for round structural components shall be calculated from the equation:
RR = .51e2 + .57 RR < 1.0
2.3.6.3 Linear appurtenances attached to a face and not extending in width beyond the normal projected area of the face may be considered as structural components when calculating the solidity ratio and wind forces.
TIAEIA-222-F
Table 1
Force Coefficients (CF) for Cantilevered ‘Ihbular Pole Structures
Round 16 Sided 16 Sided 12 Sided 8 Sided r < 0.26 r > 0.26 1 I ~32 1.20 1.20 1.20 1.20 1.20 32 to 64 013 130 1.78 + 1.4Or 915 w -cm 22.9 J2+(64-C) 125 . 44.8 am& 1.20 >64 59 1.08 1.4Or - .72 1.03 1.20 t SI Units
Round 16 Sided 16 Sided 12 Sided 8 Sided r < 0.26 r > 0.26 < 4.4 1.20 1.20 1.20 1.20 1.20 4.4 to 8.7 9.74 1.78 + 1.4Or -+5 3.78 - 1.20 (Cl I3 3% . .72 +(8k7;ooc) . Q.6 > 8.7 59 1.08 - l&r .72 1.03 1.20 C = & VDp forDpinft[m] Notes:
1. The above force coefficients apply only to cantilevered tubular pole structures which stand alone or are mounted OII the top of a latticed strwture.
2. The force coeffkients indicated account for wind load reductions under supercritica.l flow conditions and therefore do not apply to appurtenances attached to the structure.
appropriate force Coeffkients for appurtenances. Use Table 3 for 3.
4. For ail V 1s the basic wind speed for the loading condition under investigation. CTOSS sectional shapes, Cf need not exceed 1.2 for any value of C.
Table 2
Wind Direction Factors Tower Cross
Section Square
DR
1.0 1+.75e (1.2 max) 1.0 1.0 1.0 * Measured from a line normal to the face of the structureTWEIA-222-F
2.3.7 The force coefficient (CA) appkd to the projected area (ft2)
[m21 of a hxr
app~enance (AA) not considered as a ~~~ctural component shall be determined from Table 3. The force coefficient for cyli&$c~ members may be applied to the additional projected area of 0 radial i= when specified. (Refer to Figure 1.)
Table 3
Appurtenance Force CoeffkieMs
Aspect Ratio 5 7
Aspect Ratio > 25
Member Type CA CA
Flat 1.4 * 2.0
cylindrical
I 0.8 1.2
Aspect Ratio = Overti length/width ratio in plane normal to wind direction. (Aspect rstio is not a function of the spacing between support points of a linear appurtenance, nor the section length ccmidered to have a uniformly distributed force.)
Note: Linear interpolation may be used for aspect ratios other than shown.
2.3-g Regardless of location, linear appurtenances not considered as structuraI components in 0 accordance with 2.3.6.3 shall be included in the term C CA AA.
2.3.9 The horizontal force (F) applied to a section of the structure may be assumed to be mi.f~nnly distributed based on the wind pressure at the mid-height of the section.
2.3.9-l For guyed masts, the section considered to have a uniformly distributed force shall not exeed the span between guy levels.
2.3.9.2 For free-standing structures, the section considered to have auniformly distributed for= shad not exceed 60 ft [ 18 m].
2.3.9.3 For tubular steel pole structures, the section considered to have a uniformly deputed force shall not exceed 30 ft [9.1 m].
2.3.10 In the absence of more accurate data, the design wind load (Fc> on a discrete appurtenance such as an ice shield, platform, etc. (excluding microwave antennas/passive reflectors) shall be calculated from the equation:
where x CA AC considers all elements of the discrete appurtenance including any feed lines, brackets, etc., related to the appurtenance. Components of a discrete appurtenance attached directly to a tower face and not projecting away from the face may be considered as structural components when c&dating the solidity ratio and wind forces.
2.3.10.1 The velocity pressure (9z> shall be c&ulated based on the centerline height of the appurtenance.
TWEIA-222-F
2.3.10.2 The gust response factor (GH) shall be calculated based on the total height of the
stmtm for latticed structures (see 2.3.4.4) and shall be equal to 1.69 for tubular Pole smctures.
2.3.10.3 The design wind load (Fc) shall be applied in a horizontal direction in the direction of the wind.
2.3.10.4 The force coefficient (CA) applied to the projected area (fP) Cm21 of a discrete appurtenance (AC) shah be determjncd f&r Table 3. The farCe coefficient for Cysts members may be applied to the cylindrical portions of the appurtenance and to the additional projected area of ice when qecifred. (Refer to Figure 1).
2.3.10.5 When an equivalent flat-plate area based on Revision C of this standard (AF + 2/3 AR) is provided by a manufacturer of an appurtenance, a force coefficient of 2.0 must be applied to the equivalent flat-plate area when determiktg design wind loads. When the appurtenance is made up ofround members only, a force coeSzient of 1.8 may be applied. 2.3.11 In the absence of more accurate data, the design wind load on microwave antennas/passive reflectors shall be determined using Annex B.
2.3.12 When the azimuth orientations of antennas located at the same relative elevation on the stmctu.re are not specified, the antennas shall be assumed to radiate symmetrically about the structure.
23.13 shielding of antennas shall not be considered.
2.3.14 The design wind load on guy& shall be determined in accordance with Figure 2. The design wind load may be assumed to be uniform based on the velocity pressure (sz> at the midheight of each guy. .
2.3.15 The maximum member s&sses and structure reactions shall be detexmined considering the wind directions resulting in maximum wind forces and twisting moments. Each of the wind
. directions indicated in Table 2 shall be considered for latticed structures.
2.3.16 Each of the following load combinations shall be investigated when calculating the maximum member stresses and smcture reactions (see Annex A):
D+Wo D+.75W1+1
(Note: When the basic wind speed is specified as ocmning simultaneously with an ice load by the purchaser or local authority, no reduction factor shall be applied to WI.)
Wind Forces on Guys
FD = 9~ GH CD d Lc = Total drag force (lb) [NJ FL=qzGHCLdLc=Totalliftforce(lb) N
Q = Velocity pressure at mid-height of guy (lb/ft2) PAJ (see 2.3.3) k = Gust response factor based on total height of structure (see 2.3.4) d = Diameter of guy strand (ft) [m]
Lc = Chord length of guy (ft) [m]
0 = Clockwise angle from guy chord to wind direction vector (0 5 180’) CD = 1.2 sin3 8
CL = 1.2 sin28 cos 8
2.4 References
AAsH”lQ “Standard Specifications for Structural Supports for Highway Signs, LumGres atid Traffic Signals”, Ar~~erican Asso&~on of State Highway and %UlSpOrdOn Offici&
wash.@ton, DC., 1985 with 1988 interim ~pecitication~.
ma, “‘Minirn~m Design Loads for &&iiugs and Other SUUCUIXS”, Ace 7-93, An&can
Society of Civil Engineers, New York, NY, 1993.
DieU W.S., “Engineering Aerodynamics”, Revised Edition, Ronald Rress Co., New York, NY, 1936.
IAs% “Recomnendatio~ for Guy& ~ast$‘, ~temati~nal Association for Shell and Spatial S~c~eS, working Group Nr 4,1981.
LOU, T., ‘Force coefficients for ‘hnanission Towers”, A Master Research Report in Civil &&=-i.ng, Department of Civil Engineering, Texas Tech University, Lubbock, TX, 1983. sfiu, E., changery, MJ., and Fil,liben, J.J., ‘Exueme Wmd Speeds at 129 Stations in the Contiguous United States”, Building Science Series Report 118, National Bureau of Standards, Washington, D.C., 1979.
3 STRESSES 3.1 Standard
3.1-l Unless otherwise noted, structural members shall be designed iu accordance with the appropriate AISC or AISI specification.
3.1.1.1 For structures under 700 ft 1213 m] iu height, allowable stresses may be increased l/3 for both load combinations defined in 2.3.16.
3.1.1.2 For structures 1200 ft [366 m] or greater in height, allowable stresses shall not be increased.
3.1.1.3 For structures between 700 ft 1213 m] and 1200 ft [366 m] in height, allowable stresses may be increased by linear interpolation between l/3 and 0.
(Note: For structures 1200 ft [366 m] or greater in height, increases in allowable stresses do not apply due to the uncertainties of the wind effects above this height.)
3.1.1.4 Stnxture height, for purposes of determimn g allowable stresses, shall be based on the total structure height including tubular or latticed poles mounted on the structure. 3.1-l .5 Refer to 2.3.4.4 for stress increases required for cantilevered tubular pole structures mounted on latticed strucme~.
3.1.2 For guyed structures, the displacement of the mast at each guy level shall be considered wilen computing stresses.
3.1.3 The end connection and intermittent filler mqrimments of section E4 of the AI!K specification for double angle members need not be satisfied when the slenderness ratio for the buckling mode involving relative deformation between the angles is modified as follows when determining allowable stresses:
. . . . _.. - em- .
where KL
( 1 To = column slenderness of built-up member acting as a unit about the axis evolving relative deformation
a
RI = largest column slenderness of individual components
( )
F,
= modified column slenderness of built-up membera = distance between connectors
4 = minimum radius of gyration of individual component
3.1.4 A reduction coefficient equal to .75 shall be used when calculating effective net areas in accordance with section B3 of the AISC specification for angle members and other similar
members connected by one leg with one or two fasteners.
3.1.5 The reduction factor of 3.1.4 does not apply to the required investigation of block shear in accordance with section J4 of the AISC specification. Net shear and tension areas shall be based on hole diameters l/16 inch [1.6 mm] larger than bolt hole diameters.
3.16 Bolt holes shall not be considered pin holes, as referred to in section D3 of the AISC specification.
3.1.7 Deformation around bolt holes shall be a design consideration for the purposes of calculating allowable bearing stresses in accordance with section J3.7 of the AISC specification. 3.1-g Table J3.5 of the AISC specification shall ‘apply except at sheared edges where the minimum edge distance shall be 1.5 times the bolt diameter.
3.1.9 The measured unsupported length of a compression member shall be determined considering the rigidity of the connected parts and tbe direction of buckling about the axis under consideration.
3.1.10 Jn computing allowable stresses, when effective length factors are considered less than 1.00 for leg members or members whose ends are attached by a single bolt, justification of each factor must be shown by test or computation.
3.1.11 For a guyed structure, the stability of the structure between guy levels shall be considered when calculating allowable member stresses.
3.1.12 Limiting values of effective slenderness ratios for compression members shah preferably be 150 for legs, 200 for bracing, and 250 for redundants (members used solely to reduce slenderness of other members).
3.1.13 Bracing and redundants utilized to reduce the slenderness ratio of compression members shall be capable of supporting a force normal to the supported member equal to 1.5 percent of the supported member’s calculated axial load. This force is not to be applied simultaneously with the forces resulting from loads applied directly to the StruCttKe.
3.1.14 Structural Steel Single Angle Compression Members
3.1.14.1 Allowable compression stresses shall be calculated in mce with the ABC “Specification for Allowable Stress Design of Single Angle Members” except that the flexurahorsional buckling provisions do not apply.
3.1.14.2 Members subjected to lateral loads, which induce bending, shall meet the
PrO~SiOns of section 6 of the AISC specification referred to in 3.1.14.1.
3.1.14.3 Effective length factors shall be calculate&n accordance with ANSYASCE 10-90, ‘Design of Latticed Steel Transmission Towers”, hereinafter referred to as AXE 10, (See Table 4).
(Note: The effective length factors established in ASCE 10 have been adopted to adjust the ABC allowable compression stresses for the effects of eccentric axial loading and partial end restraint.)
3.1.14.4 Effective length factors, other than those specified herein, shalI be substantiated by
kStS.
3.1.14.5 Slenderness ratios (L/R) shown in Figures 3 and 4 shall be uti.Iized as a guide to cWmine measured and effective slenderness ratios.
3.1.14.6 Members shall be considered fully effective when the ratio of width to thickness (w/t) is not greater than the limiting value specified in A!XE 10.
3.1.14.6.1 When width-thickness ratios exceed the limiting value, allowable stresses shall be reduced in accordance with section 4 of the AISC specification referred to in 3.1.14.1 with Q equal to the value calculated for Fcr in AXE 10 divided by the yield stress of the member. .
3.1.14.6.2 The width w for cold-formed angles shall equal the distance from the inside
bend radius to the extreme fiber but not less than the angle width minus three times the angle thickness.
3.1.14.6.3 Width-thickness ratios (w/t) shall not exceed 25.
3.1.14.7 ASCE 10 effective slenderness curves 5 and 6 of Table 4 shall be restricted to bracing and redundant members with multiple bolt or properly detailed welded connections. In addition, connections must be to membefi having adequate flexural strength to resist rotation of the joint including the effects of gussets.
3.1.14.8 Where eccentricity at a joint cannot be avoided, due consideration shall be given to the additional stresses introduced in the members.
3.1.15 For tubular pole structures, the secondary bending moments caused by vertical loads shall be considered when computing stresses.
3.1.15.1 Allowable combined bending and axial stresses for polygonal tubular steel pole structures shall be determined from Table 5.
TIAEIA-‘22-F
Table 4
ANSI/ASCE
lo-90
EFFECTIVE SLENDERNESS CURVES
CURVES l-3
CURVES 4-6
4 I 120 k> 120
CURVE 1
CURVE 4
KL=L
KL LR R -=- R R
(CONCENTRIC BOTH ENDS) \ (NO END RESTRAINT)
CURVE 2
CURVE 5KL
-= 30 + .75k KL
R -= R ,28.6
-I-
.762i
(ECCENTRIC ONE W>
(PARTIAL
RESTRAINT
ONE
END)
CURVE 3
KL
-= 60
+
SO:R
(ECCENTRIC BOTH ENDS)
CURVE 6
KL
-=
R 46.2 + A15 k (PARTIAL RESTRAINT BOTH ENDS)
TIAXIA-Z-F
SINGLEANGLECOMPRESSION
MEMBERS
SLENDERNESSRATZOSFORLEGBRACING
SYMMETRICAL
BRACING
CRlTICAL MEASURED SLENDERNESS RATIO: 4
EF’FEC’IWE SLENDERNESS RATIOS:
L I 120 RZ L RZ > 120 CURVE 1 CURVE 4
STAGGEREDBRACING
.
Y
x
CRITICAL MEASURED SLENDERNESS RATIOS:
L
R, , & ,‘OR (’ :‘,),,
EFFECTIVE SLENDERNESS RATIOS:
i MAX I 120 k MAX > 120
CURVE 1 CURVE 4
NOTE:
FOR LEG MEMBERS, MEASURED LENGTH (L) SHALL BE
EQUAL TO THE PANEL SPACING MEASURED ALONG THE
AXIS OF THE LEG.
TIAEIA-222-F
SINGLE ANGLE COMPRESSION MEMBERS
SLENDERNESS RATIOS FOR BRACING MEMBERS
REFER TO SECTION 3.1.9 FOR
DETERMINAnON OF MEASURED
LENGTH
LLu=L1+5U CURVE2 CURVE4 * a 1 CRrIIcALMEAsuRED L, SLENDERNESS RATIO: 7 RX ORe % Ll > L2
EFFEm sLEyRNEss Iwtios:
Lx=L1+5U
i MAX 5 120 g > 120 u > 120 RZ
cLJRvE2 CLiRVE6 CURVE5
Note:
For bracing members with welded or two or more bolt cxmections, measured length (L) Shall not be less than the distme between the cemroids Of the ~nnectiolls at each end. Properly detailed welded c.onnectiom may be considered as providing partial restraint.
3.1.16 The design of reinforced concrete for foundations and guy anchors shall Conform to me “Building Code Requirements for Reinforced Concrete” (AC1 318-89) issued by the American Concrete Institute.
3.1.16.1 For structures under 700 ft [213 m] in height, the required reinforced concrete strength shall equal 1.3 times the full structure reactions produced by each load combination defmed in 2.3.16.
3.1 J6.2 For structures 1200 ft 1366 m] or greater in height, the required reinforced concrete strength shall equal 1.7 times the full structure reactions produced by each load combination defined in 2.3.16.
3.1.16.3 For structures between 700 ft [213 m] and 1200 ft 1366 m] in height, the required
reinforced concrete strength shall be determined by linear interpolation between 1.3 and 1.7 times the structure reactions.
3.1.16.4 Structure height, for purposes of de tennhing required reinforced concrete sue@& shall be based on the total structure height including tubular or latticed poles mounted on the structure.
Table 5
Allowable Combined Bending and Axial Stresses for Polygonal ‘lobular Steel Pole
Structurt!s
Compact Sections F~=.60Fy
Noncompact Sections 16 Sided
215 c &w/t c 365 ‘Fyin ksi 565 < & w/t : 958 FyinMPa FB -852 Fy (CO - 0.00137 ,& w/t) ksi FB = .852 Fy (1 .O - 0.000522 ,&w/t) MPa 12 Sided 240 < &w/t < 365 Fyin ksi
630 < &w/t 2 958 FyinMPa FB -870 Fy (TO - 0.00129& w/t) ksi FB = .870 Fy (1.0 - 0.000491 ,/&w/t) MPa 8 Sided 260 c &w/t < 365 Fyinksi
683 7 &w/t 2 958 FyinMPa FB =.852 Fy (TO - 0.00114,/& w/t) ksi FB = .852 Fy (1.0 - 0.000434 & w/t) MPa FB = Allowable combined bending and axial stress
Fy= Yield strength t = Wall thickness
w = Actual flat side dimension, but not less than dimension calculated using a bend radius equal to 4t
Note: Equations obtained from EPRI report TLMRC-87-R3, “Local Buckling Strength of Polyg- onal Tubular Poles”, April 1987.
IIA/klA-122-F
4 MANUFACTURE AND WORKMANSHIP 4.1 Standard
4.1.1 Manufacturing and worha&ip shall be in accordance with CO-@ accept&
standards of the structural steel fabricating industry.
4.1.2 Welding procedures shall be in accordance with the requirements of the aPProPfiate AISC or AISI specifications.
5 FACTORY FINISH 5.1 Standard
51.1 In the absence of other specific requirements, all materials shall be galvanized (see Annex A).
5.1.1.1 SUUCtUra.lMate~~ - S~I-UC~~ ~taials shall be galvanized in accordance with ASTM A123 (hot-dip). Exceptions may be made when galvanizing in accordance with ASTM A123 would be potentially detrimental to the structure or its components. Examples include applications utilizing certain high-sue@ and/or proprietary steels and weldments. In these cases, an alternative method of corrosion control shall be specsed.
5.1.1.2 Hardware - Hardware shall be galvanized in accordance with ASTM Al53 (hot-dip) or ASTM B695 Class 50 (mechanical).
5.1.1.3 Guy Strand - Zinc-coated guy strand shall be galvanized in accordance with ASTM A475 or ASTM A5S6.
a 6 PLANS, ASSEMBLY TOLERANCES, AND MARKING
6.1 Standard .
6.1-l Complete p1a.r~ assembly drawings, or other documentation shall be supplied showing the necessary marking and details for the proper assembly and installation of the material, including the design yield strength of the spuctural members and the grade of structural bolts required.
6.1.2 Tolerances for the proper layout and installation of the material; and the foundations and
anchors shall be shown on the plans.
6.1.2.1 Plumb - The horizontal distance between the vertical centerlines at any two
elevations shall not exceed 25 percent of the vertical distance between the two elevations. 6.1.2.2 Twist - The twist (angular’ rotation in the horizontal plane) between any two elevations shall not exceed 0.5O in 10 feet [3 m] and the total twist in the structure shall not exceed 5’.
6.1.2.3 Length - For tubular steel pole structures with telescoping joint, butt welded or flanged shaft connections, the overall length of the assembled structure shall be within plus 1 percent or minus l/2 percent of the specified height.
(Note: Horn reflectors and other types of offset-feed antennas have polarization performance requirements, which are sensitive to ar+@ar displacement from boresight e direction. Special consideration must be given to the mount, attachment hardware, installation practice, as well as the support structure, to minimize all contributing factors to initial skew or offset.)
6.1.3 All structural members or welded structural assemblies, except for hardware, shall have a part number. The part numbers shall correspond with the assembly drawings. The Part number is to be permanently attached (stamped, welded lettering, stamped on a plate that is welded to the member, etc.> to the member before all protective coatings (galvanizing, paint, etc.1 are aPPhed. The part number shall have a minimum character height of l/2 in. [13 mm], be legible and clearly visible to an inspector after erection.
7 FOUN-DAnONS AND ANCHORS 7.1 Definitions
7.1.1 Standard Foundations and Anchors - Structures designed to support the specified loads defined in Section 2 for normal sod conditions as defined in 7.1.3. Pile construction, roof msmations, foundations or anchors designed for submerged soil conditions, etc., are not to be considered as standard.
7.1.2 NonS tandard Foundations and Anchors - Structures designed to support the specified loads defined in Section 2 in accordance with site specific conditions.
7.1.3 Normal Soil - A cohesive soil with an allowable net vertical bearing capacity of 4000 pounds per square foot Cl92 kPa] and an allowable net horizontal pressure of 400 pounds Per
square foot per lineal foot of depth [63 kPa per lineal meter of depth] to a maximum of 4~00 pounds per square foot 1192 pa].
(Note: Rock noncohesive soils, saturated or submerged soils are not to be considered normal a
soil.)
7.2 Standard
7.21 Stanchi foundations and anchors may be used for bidding purposes and for construction when actual soil pa&meters equal or exceed normal soil parameters.
7.22 When standard foundations and anchors are utilized for final designs, it shaU be the responsibility of the purchaser to verify by geotechnicai investigation that actual site soil parameters equal or exceed normal soil parameters. (See Annex A.)
7.2.3 Foundations and anchors shah be designed for the maximum structure reactions resulting from the specified loads defined in Section 2 using the following criteria:
7.2.3.1 When standard foundations and anchors are to be used for constnrction, “normal
soil” parameters from 7.1.3 shall be used for design.
7.2.3.2 When nonstandard foundations and anchors are to be used for construction, the soil parameters recommended by the geotechnicai engineer should incorporate a minimum factor of safety of 2.0 against &imate soil strength (see Annexes A and I).
7.2.4 Uplift
7.2.4.1 Standardf oun d ti a ons, anchors, or drilled and belled piers shall be assumed to resist uplift forces by their own weight plus the weight of earth enclosed within an inverted
pyramid or cone whose sides form an angle of 30’ with the vertical. The base of the cone shall be the base of the foundation if an undercut or toe is present or the top of the foundation
base in the absence of the foundation undercut. Earth shall be considered to weigh 100 pounds per cubic foot [16 kN/n$] and concrete 150 pounds per cubic foot [24 kN/m3].
I rA~!zlA-222-F
7.2.4.2 Straight shaft drilled pien for st&ad foundations shall have an ultimate skin
friction of 200 pounds per square f00t pa lineal foot of depth [31 kPa per Iineal meter of
d@l to a maximum
of 1000 pounds per square foot of shaft surface area 148 kpal for upllfr or download resistance.7.2.4.3 Nonstandard foundations, anchors, ami &i.lkd piers shall be designed in awodance with the recommendations of a geotechnid report (see Annex I).
7.2.4.4 Foundations, anchors, and drilled piers shah be proportioned in accordance with
the following:
(WR /2-o) + (WC D-25) 2 Up and (wR+wc)/l.5 1 up
where: WR = soil resistance from 7.2.4.1.7.2.4.2 or 7.2.4.3 WC = weight of concrete
Up = maximum uplift reaction
7.2.4.5 A mat or slab foundation for a seif-supporting structure shall have a minimum safety factor against overturning of 1.5.
7.2.5 The depth of standard drilled foundations subjected to lateral or overturning loads shall be proportioned in accordance with the following:
LD 2 2.0 + S/(3d) + 2 [S2/(18d2)+ S/2 + M/(3d)]ln (ft)
LD > .61 + S/(143d) + 2 [S2/(41333d2) + S/96 + M/(143d)11R [ml where:
.
LD = Depth of drilled foundation below grounilevel (ft) [ml
d = Diameter of dri.Ued foundation (ft) [ml S = Shear reaction at ground level (kips) &NJ
M = Ovemuning moment at ground level (ft-hips) [m-w
Reference: Broms, B., “Design of Laterally Loaded Piles”, Journal of the Soil Mechanics and Foundation Division Proceedings of the American Society of Civil Engineers, May, 1965.
7.3 Special Conditions
7.3.1 When a support is to be designed by other than the manufacturer, the manufacturer will
be responsible for furnishing the reactions, weights, and interface details for the purchaser’s engineer to provide the necessary attachment.
7.3.2 The effects of the presence of water shall be accounted for in the design of nonstandard foundations. Reduction in the weight of materials due to buoyancy and the effect on soil properties under submerged conditions shall be considered.
7.4 Foundation Drawings
7.4.1 Foundation drawings shd indicate structure reactions, material strengths, dimensions, reinforcing steel, and embedded anchorage material type, size, and location. Foundations desiped for nomA soil conditions shall be so noted.
(Note: Normal soil design parameters and methods are presented to obtain uniform standard foundation and anchor designs for bid&g purposes. Design methods for other COnd~OnS and 0t.k foundation types must be consistent with accepted engineering practices.)
8 SAFETY FACTOR OF GUYS 8.1 Definition
8.1.1 Guy Connection - The guy connection is defmed as the hardware or mechanism by which a length of guy strand is connected to the tower, insulator, or guy anchor. The connection may include, but is not limited to, the following: shackles, in-line insulators, thimbles, turnbuckles, twin base clips, u-bolt cable dips, poured socket fittings, and grip- type dead-end
connections. ‘l%vin base and u-bolt chps used on guy strand through 7/8-in. diameter shall be considered to have a maximum efficiency factor of 90 percent. In all other cases, clips on strand shall be considered to have a maximum efficiency factor of 80 percent. For all other types of end connections, manufacturer’s recommendations should be followed when determining the connection efficiency factor,
8.1.2 Safety Factor of Guys - The safety factor of guys shall be calculated by dividing the published breaking strength of the guy or guy connection strength, whichever is lower, by the maximum calculated tension design load.
8.2 Standard
8.21 For structures under 700 ft [213 m] in height, the safety factor of guys and their connections shall not be less than 2.0.
8.2.2 For structures 1200 ft [366 m] or greater in height, the safety factor of guys and their connections shall not be less than 2.5.
8.2.3 For structures between 700 ft [213 m] and 1200 II [366 m] in height, the minimum safety factor of guys and their connections shall be determined by linear interpolation between 2.0 and 2.5.
(Note: A l/3 increase in stress for wind-loading conditions does not apply to the published breaking strength of guys and their connections.)
8.2.4 Structure height, for purposes of determinin g the required safety factor of all guys and their connections, shall be based on total structure height including tubular or latticed poles mounted on the structure.
9 PRESTRESSING AND PROOF LOADING OF GUYS 9.1 Definitions
9.1.1 Prestressing of Guys - The removal of inherent constructional looseness of the guy under a sustained load.
9.1.2 Proof Loading - The assurance of mechanical strength of factory assembled end connections.
- -.. _ _-- a
9.2 Standard
9.2.1 &stressing and proof loading are not normaLly required. When specified. Presnessing and proof loading shall be performed in accordance with the recornmendati~~ of the gUY manufacturer.
(Note: For tall, guyed structures, consideration should be given to prestressing and Proof loading.)
10 INITIAL GUY TENSION 10.1 Definition
10.1-l Initial Guy Tension - The specifieci guy tension in pounds [newtons] under no wind
load conditions, at the guy anchor at the specified temperature (see 10.2). 10.2 Standard
10.2.1 Initial tension in the guys, for design purposes, is normally 10 percent of the published breaking strength of the strand with upper and lower limits of 15 and 8 percent respectively. Values of initial tension beyond these limits may be used provided consideration has been given to the sensitivity of the structure to variations in initial tension and, if necessary, to dynamic behavior (see note below). Consideration shall be given to the site ambient temperature range. In the absence of site specific data, the initial tensions shall be based upon an ambient temperature of 6O*F.
(Note: The stated 8-15 percent initial tension extreme values are provided as recommended guidelines only. Specific site and terrain conditions may necessitate initial tension values outside this range. When using initial tension values above 15 percent, consideration should be given to the possible effects of aeolian vibration. mewise, when using initial tension values less tha.u g percent, consideration should be given to the effects of galloping and slack-taut pounding.)
10.3 Method of Measurement
10.3.1 Initial tension may be measured by vibration frequency, mechanical tensiometers, ~eas~~ent of guy sag, or by other suitable methods (see Annex E).
11 OPERATIONAL REQUIRE,MENTS 11.1 Definitions
11.1.1 Twist - The angular rotation of the antenna beam path in a horizontal plane from the no-wind load position at a specified elevation.
11.1.2 Sway - The angular rotation of the antenna beam path in a vertical plane from the no-wind load position at a specified elevation.
11.1.3 Displacement - The horizontal translation of a point relative to the no-wind load position of the same point at a specified elevation.
11.2 Standard (See Annex A)
11.2.1 Theminim Urn standard shall be based on a condition of no ice and a wind load based on a 50 mph basic wind speed [22.4 m/s] calculated in accordance with 2.3. The operational requirements shall be based on an overah allowable 10 dI3 degradation in radio frequency signal level.
11.2.2 Unless otherwise specified, the operational requirements for micrOWaVe antex&
reflector systems shall be determined using Annexes C and D. 12 FWXECITVE GROUNDING
12.1 Definitions
12.1.1 Grounding - The means of establishing an electrical connection between the structure and the earth, adequate for lightning, high voltage, or static discharges.
12.1.2 primary Ground - A wnchcting connection between the structure and earth or some
conducting body, which serves in place of the earth.
12.1.3 Secondary Ground - A conducting connection between an appurtenance and the structure.
(Note: Ground wire should not be encased in the foundation.)
12.2 Standard (See Annex A)
12.2.1 Structures shall be directly grounded to a primary ground.
12.2.2 A minimum ground shail consist of two 98 in. [16 mm] diameter galvanized stee! ground rods driven not less than 8 ft [25 m] into the ground, 180* apart, adjacent to the stmcmre base. The ground rods shah be bonded with a lead of not smaller than No. 6 [5 mm] tinned bare copper connected to the nearest leg or to the metal base of the structure. A similar ground rod shall be installed at each guy anchor and similarly connected to each guy at the anchor. 12.2.3 Self-supporting towers excee&ng 5 ft [1.5 m] in base width shall have one ground rod per leg installed as above.
12.2.4 All equipment on a structure shah be connected by a secondary ground.
12.2.5 Remote passive reflectok are exempt from the grounding requirements specified herein. 13 CLMMNG AND WORKING FACZIUTJES
13.1 Definitions
13.1.1 Climbing Facilities - Components specifically designed or provided to permit access, such as fixed kkhs, step bolts, or snuctu.ral members.
13.1.2 Climbing Safety Devices - Equipment devices other than cages, designed to minimize accidental falls, or to Iitnit the distance of such falls. The devices permit the person to ascend or descend the structure without having to continually manipulate the device or any part of the device. The climbing safety device usually consists of acarrier, safety sleeves, and safety beits.
13.1.3 Working Facilities - Work platforms and access runways.
13.1.4 Hand or Guardrds - Horizontal barriers erected along the sides or ends of working
facilities to prevent falls. 13.2 Standard
13.2.1 Climbing and working facilities, hand or guardrails, and climbing safety devices shall be provided when specified by the purchaser. (See Annex A.)
13.2.2 Climbing facilities shah be designed to support a minimum 250 [l.l kN] pound concentrated live load.
TIAEIA-222-F
13.2.2.1 When fmed ladders are specified as the climbing facility, they shall meet the fo~o~g minimum requirements:
a. Side rail spa&g - 12 in. [300 mm] minimum clear width.
b. Rung spacing - 12 in. [30O mm] minimum center-to-center, 16 in. [410 mm] maximum.
C. Rung diameter - 5/8 in. [16 mm] minimum.
13.2.2.2 When step bolts are specified, they shall meet the following requirements: a. Clear Width - 4 l/2 in. [llO mm] minimum.
b. Spacing - 12 in. minimum [300 mm] center to center, alternately spaced, 18 in. 1460
mm1
maximum.c. Diameter - 5/S in. 116 mm] minimum.
13.23 Climbing safety devices shall meet the design requirements of the American National Standards Institute (ANSI) A14.3-1984, “Safety Requirements for Fixed Ladders”, Se&on 7.
13.24 Support structures for working facilities shall be designed to support a uniform live load of 25 lb/ft’ Il.2 kpa], but in no case shall the support structure be designed for less than a total he load of 500 pounds 12.2 ItN]. Working surfaces, such as grating, shall be designed to support
two 250-pound [ 1.1 IrN] loads. These loads are not to be applied concurrently with wind and ice loads.
132.5 Hand or guardrails shall be designed to support a minimum concentrated live load of 150 pounds LO.67 kN1, applied in any direction. .
(Note: 13.2 is intended to provide m,i,nim m requirements for new structures. It is not intended to replace or supersede applicable laws or codes.)
14 -ANCE AND INSPECTION 14.1 Standard
14.1.1 Maintenance and inspection of steel antenna towers and antenna supporting structures should be performed by the owner on a routine basis.
(Note 1: It is recommended that all structures be inspected after severe wind and/or ice storms or other extreme loading conditions.) ,
(Note 2: Recommended inspection and maintenance procedures for towers are provided in
Annex E.)
(Note 3: Shorter inspection intervals should be considered for structures in coastal salt water
environments, in corrosive atmospheres, and in areas subject to frequent vandalism.) 15 ANALYSIS OF EXNING TOWERS AND STRUTS
15.1 Standard
15.1-l Steel antenna towers and other suppo~g stNctures should be analyzed when changes occur to the original design or operational loading conditions. Recommended criteria for the analysis of existing structures are provided in Annex F.
16 COUNTY LISTINGS OF MINIMUM BASIC WIND SPEEDS (See Annex A) c0uNl-Y statf! of ALABAMA AUTAUGA BALDWIN BARBOUR BIBB BLOUNT BULLOCK BUTLER CALHOUN CHAMBERS CHEROKEE (ZTHIEDN CHOCTAW E!tt&mE COFFEE COLJ3lXT CONECUH COOSA COVING-l-ON CRENSHAW DALE DALLAS DEKALB ELMORE EscAMBIA ErowAH FAYEITE GENEVA BENRY HOUSTON JACKSON JEFFERSON LAUDERDALE LAmcE LIMESTONE LOwNDE!z MACON MADISON MARENGO MARION MARSHALL MOBILE NOTE* 2 2 2 2 2 2 2 2 2 2 2 2 2 2 BASIC WIND s=ED(Mpm 70 100 75 70 70 ii 70 70 70 70 ii: 70 70 85 70 85 ii 80 70 80 70 70 70 90 70 70 70 90 70 70 80 85 70 70 70 70 70 70 70 75 70 70 75 70 70 95 *For notes, see end of Section 16
StatedALABAMA
BASIC WIND
COUNIY NOTE* SPEED(MpH)
MONROE 2 MONTGOMEEtY MORGAN PERRY FICKENS iEFDOiJ?H 2 RUSSEL SAINTCLAIR SHEBY tiZ!it~GA TALLAPOOSA TUSCALOOSA WALKER WASHINGION 2 WILCOX 2 WINSTON
-
85
70 70Ei
75 70 70*
70 70 70 70 70;
:
70 state of ALASKA ALEunANIsLANDs ANCHORAGE I=?= BRISTOL BAY DILLINGHAMFAlRBANKS NO. STAR JUNEAU KENAIFENINSULA KEKEEANGAXEWAY KOBUCK KODIAK ISLAND; WANUSKA-SUSl’INA NOME NORTH SLOPE PRINCEOFWALES SIlKA SKAGWAY-%4KUTfl- ANGOON SOUTHEASTFAIRBANKS VALDEZ-CORDOVA WADEHAMPTON wRANGELt--URG YUKON-KOYUKUK
caution: Mound regicm af Alaskashouidbecxmsidered~ sYpdaiwin.dregions. 110 110 110 105 105 70 80 90 100 95 100 110 80 110 100 100 100 100 70 90 110 90 90
State of ARIZONA
BASIC WIND
COUNTY NOTE* mED(MpH)
APACHE 1 COCBlSE cocoNINo 1 FEGAM LAPAZ MARICOPA MOHAVE NAVAJO 1 PINAL SANTACFUJZ YAVAPAI State of ARKANSAS ARKANSAS ASHLEY BAXIER BENTON BOONE BRADLEY CALHOUN CARROLL CBICOT CLAY EkG%!E% COLUMBIA CONWAY CRAIGHEAD CRAWFORD CRm-ENDEN CROSS DALLAS DESFIA DREW FAULKNER FUIXON GARLAND HEMPSTEAD HOT SPRING 70 70 70 E 70 70 75 75 70 75 75 70 75 70 70 70 70 70 70 , 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 couIvIY sta!eofARKANsAs BASIC WIND SPEEDWR) NOTE* HOWARD INDEPENDENCE JACKSON JEFFERSON JOHNSON WA- LAWRENCE IJNCOLN LmuzRrvER LOGAN LONOKE MADISON MARION MISSISSIPPI MONROE MONTGOMERY NEVADA NEWIUN OUACHITA PERRY PHILLIPS P0Ixm-r PO= POPE iiiiEsI RANDOLPH sAINrFIuNas SALINE scorr SEARCY SEBASTIAN EE SroNE UNION VANBUREN WASHINGTON WOODRUFF 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70
1 IA/tlA-7”- F state of CALIF0RNr.A COUNTY NOTE* ALAMEDA ALPINE AMADOR BUTTE CALAVEMS COLUSA CONTRA COSTA DELNORTE ELDORADO FRESNO HUMBOLDT EEi KINGS LASSEN LOS ANGELES MADEwi MARIPOSA MENDocmo MEWED MODOC MONO MONTEREY NAPA NEVADA ORANGE PLACER PLUMAS -IDE SA- SANBWO SANBERNARDINO SANDIEGO sANFRANcIsc0 SAN JOAQUIN SANLUIS OBISPO sANlkulEo SANTABARBARA SANTACLARA SANTACXJZ SHASTA 1 SEE&4 1 a SISKIYOU 1 SOLANO SONOMA 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 BASIC WIND SPEED0 70 70 70 75 70 75 70 80 75 70 ii 70 70 70 ii 75 70 70 75 ii: 70 70 70. 70 75 75 70 75 70 70 75 70 70 70 70 70 70 70 70 70 70 75 70 75 75 80 stateafcALIFom BASIC WIND
COUNTY NOTE* SPEED (MPM
state of coLoRAD ADAMS ALAMOSA ARAPAHOE AR- BACA BENT BOULDER CLEARCREEK CONEIOS cosm CROWLEY CUSTER DEtTA DENVER DOLORES DOUGLA!3 EAGLE ET& FREMONT GARFIELD GlLPlN iiii%iON BINSDALE HUERFANO JACKSON JEFFERSON KIOWA KIT CARSON LAPLCA 1 1 1 1 1 1 1 1 1 1 1 1 70 75 75 80 70 70 70 75 75 85 ii 70 85 85 85 80 85 85 80 80 85 80 70 85 70 85 80 E 80 80 85 85 75 70 ii ii 85 80 70 85 *For notes, see end of Section 16
1 lAftlA-7”-t a--
state of COLORADO StateiofFLORIDA
BASIC WIND
COuNlY NOTE* SEED0
LASAMMAS LINCOLN LOGAN MESA MOFEAT MONTEZUMA MONlROSE MORGm OlERO OURAY PARK PHILLIPS PIIXIN FROWERS PUEBLO RIO BLANC0 RIO GRANDE ROUTT SAGUACHE SANJUAN SANMXGUEL SEDGWICK SUMMIT 1.m WASI-BNGTON 1 80 E 70 75 80 70 ii 85 70 1 80 85 80 85 85 ii 85 1 80 70 ii 1 80 1 85 85 85 85 stare of CONTvEcl-ICUT FAIRFIELD 2 85 HAKl-FORD 2 80 Lrrm 1.2 80 MIDDLESEX 2 85 NEWHAVEN 2 85 NEWLONDON 2 85 TOLLAND 2 85 WINDHAM 2 85 State of DELAWARE 2 80 NEW CASTLE 2 75 SUSSEX 2 90 Disnict of COLUMBIA DISTRICTOF COLUMBIA 2 75 COUNTY ALACEIUA B- . BAY BRADFORD BREVARD BROWARD CALHOUN CHARLOTIE CnRus CLAY COLLIER COLUMBIA DADE DE SOT0 DIXIE DW& ESCAMBIA FLAGLER GADSDEN GILCHRIST GLADES HAMILTON HARDEE BENDRY .IiiERNANDo HIGHLANDS HILLSBOROUGH HOLMES fNDIANRlvEEz JACKSON JEFFERSON LAFAYEI-IE LEON LTBERTY MADISON MANATEE MARION MONROE NASSAU OKALOOSA OKEJXHOBEE NOTE* 2 1 2 2 2 2 2 2 2 2 2 2 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 ; : 2 BASIC WI-ND SPEED0 95 90 100 95 105 115 100 105 100 95 110 90 115 105 100 95 100 100 105 95 95 100 105 90 100 105 105 100 105 95 105 95 95 95 100 105 95 100 100 95 105 100 105 120 95 1M) 100
1 l&&IA-~- F
State ofFLORIDA State of GEORGIA
BASIC WIND
COUNTY NOTE* sPEEDo COUNIY NOTE*
ORANGE 2 100 OSCEOLA 2 100 PALMBEACH 2 110 PMCO 2 105 PINELLAS 2 105 F0I.K 2 100 PUTNAM 2 95 SAINTJOHNS 2 loo SAINTLUCIE 2 105 SANTA ROSA 2 100 SARASOTA 2 105 SEMINOLE 2 100 SUMTER 2 100 SUWANNEE 2 90 TAmOR 2 100 UNION 2 95 VOLUSIA 2 100 WAKULLA 2 100 WALTON 2 100 WASHINGTON 2 95 State of GEORGIA APPLING MKINSON BACON BAKER BALDWIN BANKS BARROW BARTOW BENHILL BERRIEN BIBB BLECKLEY BRANTIXY BROOKS BRYAN BULLOCH BURKE BUTTS CALHOUN CAMDEN CANDLER CARROLL CMOOSA -TON 2 2 2 2 2 2 2 2 2 85 .80 85 80 75 75 75 75 80 80 70 75 90 85 90 85 80 70 75 95 80 70 70 90 95 mAHoocHEE (ZHtUTOOGA CBEEIOKEE CLAY CLAYTON CLJNCH COBB COFFEE c0LQm-r COLUMBIA COOK COWEIA CRAWFORD CRTSP DADE DAWSON DECQUR DEKALB DODGE DOOLY DOUGBEKIY DOUGLAS =Y ECXOLS EFFINGHAM ELBEEa EVANS FANNIN FAYEITE FLOYD FORSYTH FULTON GLASCOCK GLYNN GORDON K HABERBAM HANCOCK HAULSON BASIC WIND SPEEDm 70 75 70 75 75 70 85 70 * 80 80 75 80 70 70 75 70 75 90 70 75 75 75 70 80 85 90 75 80 85 70 70 70 75 75 70 70 75 95 70 85 75 75 75 75 75 70 70 75 70
TIAEIA-‘22-F State of GEORGIA I COUNTY HENRY HOUSTON it--ON JASPER JEFFDAVIS JEFFERSON JENKINS JOHNSON JONES iI%E LAURENS LIBERTY LINCOLN LONG LOWNDES LUMPKIN MACON MADISON MARION MCDUFFIE MCINTOSH MlTcHEu MONROE MONTGOMERY MORGAN MURIUY MUSCOGEE NEWTON OCONEE OGLEl-HORPE PAULDING PEACH PICKENS PIERCE PIKE POLK PULASKI PUTNAM Q- RABUN RANDOLPH RICHMOND ROCKDALE NOTE* 2 2 2 2 BASIC WIND sPJ330 70 ii 75 75 80 75 80 75 75 70 85 75 75 90 75 90 85 75 70 75 70 75 95 70 80 80 70 80 75 70 70 75 75 75 70 70 75 90 70 70 75 75 75 70 75 75 70
cow
EEEN
SEMINOLE SPALOING kFE%F State of GEORGIA BASIC WIND NOTE* SPEED (Mm 70 liW3OT -0 3lxrrNALL TAnOR zEiz% THOMAS TOOMBS TOWNS 2 2 TROUP TWIGGS UNION UPSON WAIXER WAIXON EEEN WASHlNG’IDN WAYNE itziEz 2 80 2 85 70 75 70 70 70 75 * 2 85 70 80 75 8s 80 85 70 80 70 75 75 70 70 75 75 2 85 75 75 2 90 70 WILCOX WILKINSON WORTH 80 70 70 75 75 75 75 state OfHAwAlI HAWAII HONOLULU KAUAI MAUI 80 80 Emistate of IDAHO COuNm ADA ADAMS BANNOCK BEARLIKE BENEWAH BINGHAM BLAINE BOISE BONNIER BO- BOUNDARY BUTIE CAMAS CANYON CARIBOU CASSIA CLEARWMER CUSTER ELMORE FREMONT GOODING IDAHO JEFFERSON JEROME K00TENAI L.f%rM Et2 LINCOLN MADISON MINIDOKA NEZPERCE ONEIDA OWYHEE PAYEITE POWER SHOSHONE TETON TWINFALLS VALLEY WASHINGTON NOTE* 1 I BASIC WIND sPEED(Mpm 70 70 70 75 70 70 70 70 70 75 70 70 70 70 75 70 70 70 70 70 70 75 70 70 70 70 70 70 70 70 70 70 75 70 70 70 70 70 70 70 75 70 70 70
a
*For notes, see end of Section 16state of xLLIN01s
BASIC WIND
COUNTY
NOTE* SF'EED(MpmIzE4DER
BOND BOONE BROWN BUREAU CAUIOUN CARROLL ~Z~ELPAIGN CHRISTIAN .- CLAY CUNTON COXES COOK CRAWFORD CUMBW DEKALB DEWl’IT DOUGLAS DU PAGE EDGAR EDWARDS EFFINGHAM FAYEITE FORD FULTON GALJXlTV GRUNDY HAMILTON HANCOCK iii%i:SON BENRY IROQUOIS JACJLSON JASPER JEFFERSON JERSEY JO DAVIESS JOHNSON KENDALL KNOX 70 70 70 80 70 75 ii 70 70 ii 70 70 70 75 70 70 75 70 70 75 70 70 70 70 70 70 70 70 70 75 70 75 70 75 75 75 70 70 7@ 70 80 70 75 75 75 75TIAEIA-222-F state of ILLINOIS COUNTY LASALLE LAWRENCE LIVINGSTON LOGAN MACON MACOUPIN MADISON MARION MARSHAL;L MASON MASSAC MCDONOUGH MCBEN-RY MCLEAN MENARD MERCER MONROE MONTGOMERY MORGAN MOULIRIE OGLE PEmIA PERRY PIAIT PIKE POPE PULASKI PUTNAM RANDOLPH kG SAINTCL4IR SALINE SANGAMON SCHLJYBZ SCOTT SHEIJ3Y STARK STEPHENSON TAZEWELL UNION VERMILION WABASH WARRJ3 WASHINGTON WAYNE BASIC WIND NOTE* SPEED0 1 80 75 70 75 75 70 70 70 70 70 75 70 70 70 80 70 70 75 70 70 70 ii: 75 70 70 70 70 70 75 70 70 75 70 70 70 70 70 70 75 80 70 70 70 70 ; 70 70 stateoflLLINoIs BASIC WIND
CouNn NOTE* SPE’EDWm
WHITESIDE 80 %AMSON 75 70 WINNEBAGO 80 WOODFORD 75 StatedINDIANA ADAMS BARTHOLOMEW BENTON BLACKFORD BOONE BROWN CARROLL CASS E&ON CRAWFORD DAVIESS DEARBORN DECQTJR DEXAL33 DELAWARE DUBOIS FAYEI-IE FLOYD FOUNTAJN FUIXON GIBSON EEk HAMIIXON HANCOCK HARRISON HENDRxcKs HENRY HOWARD HUNTINGION JACKSON JASPER JAY JERER!ZON JENNINGS JOHNSON 75 75 70 75 70 70 70 70 75 70 70 70 70 70 70 70 75 70 70 75 70 70 70 70 75 70 70 70 70 70 70 70 70 70 75 70 75 70 70 70 70
State ofINDIANA
BASIC WIND
COUNTY NOTE* SPEED0
KNOX KoscIusKo LAPORTE LAGRANGE LAWRENCE MADISON MARION MARS= iEkE? MONROE MONTGOMERY MORGAN NEWTON NOBLE OHIO ORANGE OWEN PARKE PERRY PIKE
e
PORTER POSEY PULASKI mAM RANDOLPH RUSH ST. JOSEPH SCOTT SI3Eu3Y SPENCER STARKE STEUBEN SULLIVAN S- TIPPECANOE TIPTON UNION VANDERBURGH VERMIIUON VIGO WABASH WARREN WARRICK WASHINGTON 70 75 1 75 75 1 75 70 70 70 75 70 75 70 70 70 75 75 70 70 70 70 70 70 1 75 70 75 70 70 70 70 75 :8 70 75 75 70 70 70 70 70 70 70 70 75 70 70 70 70 WAYNE*For notes, see end of Section 16
; TIAEIA-222-F StatedINDIANA BASIC WIND COUNTY NOTE* SF=D(MpH) State af IOWA
ADAXR
2i?izLE
. APPANoosE
AUDUBON BENTON BLACKHAWK BOONE BREh4ER BUCHANAN BUENAVISTA BUTLER CALHOUN CARROLL CASS WAR cER.RoGoRDo -0KEE CHICKASAW CLARKE CLAY CLAYTON CLINTON ClUWFORD DALLAS DAVIS DECAI’UR DELAWARE DES MOINES DICKINSON DUBUQUE ft%EE FLOYD FREMONT GRUNDY ZN HANcocK 80 80 Fl 80 80 ii 80 80 80 80 80 80 80 80 80 80 80 80 80 80 80 80 80 75 80 80 75 80 80 80 80 80 80 80 ix 80 80 80TlAIEIA-221-F State of IOWA COUNTY HARDIN HARRISON HENRY HOWARD HUMBOLDT IDA IOWA JACKSON JASPER JEFFERSON JOHNSON JONES KEOKUK KossuIH LOUISA LUCAS LYON MADISON MAHASKA MARION MARSHALL MITCBELL MONONA MONROE MONTGOMERY MWXKINE O’BRIEN OSCEOLA PACE PALO ALTO PLYMOUTH POC4HONTAS POLK BASIC WIND NOTE* sPEEDch4Pm POTTAWAmAMlE P0wl3HlEK RINGGOLD SAC SCOTr SHELBY SIOUX STORY TAMA TAnOR UNION VANBUREN WAPEILO
*For notes, see end of Section 16 75 80 80 80 80 80 80 80 80 80 80 80 75 80 75 80 85 80 80 80 80 80 80 80 80 80 80 80 ii 80 ix 80 80 80 ;z 80 80 85 80 80 80 80 75 80 State dIOWA BASIC WIND
COUNTY NOTE* SPEEDWH)
WARREN WASHINGTON WAYNE WEBSTER WJNNBBAGQ WINNES- WOQDBURY WOKm WRIGHT State &KANSAS . ANDERSON AKHISON BARBBR BARH3N BOURBON BROWN BUILBR CHASE CHATAUQUA CHEROKEE EEED EiEkBE COWLJZY CRAWFORD DECATUR DICKINSON DONIPHAN DOUGLAS EDWARDS Es mLswoRlH 75 iFi 80 80 70 80 80 80 75 70 85 80 80 80 75 80 80 70 ii: 80 80 80 ii: 80 85 85 75 80 85 85 85 85
State of KANSAS
BASIC WIND
COUNIY NOTE* SPEED0
=OD 85 75 HAMILTON ii iiEE 80 85 HODGA4AN 85 JACKSON 80 JEFFERSON xi JOHNSON 75 85 KINGMAN 80 KIOWA 80 LABErIE 70 =VJZNWORTH ii LINCOLN 80 2i.N 75 85 LYON 80 MARION MARSHALL MCPHERSON MEADE iEG!iaL MONTGOMERY MORRIS MORTON NEOSHO NESS NOKI’ON OSAGE OSBORNE C7ITAWA PAWNEE PHILuPS POTI-AWATOMIE RAWUNS RENO REPUBLIC RICE ROOKS RUSH
80
80 80 85 75. 80 75 80 85 80 75 85 85 80 80 80 80 85 80 80 85 80 80 80 80 85 85 RUSSELL 80*For notes, see end of Section 16
State uf KANSAS
BASIC WIND
COUNTY NOTE* SPEED(MpH)
EEiORD STANTON STEVENS IHOMAS TREGO WABAUNSEE WUCE WASHING’IDN WI-A WILSON WOODSON WYANDm state of KENTCJCKY . ADAIR ANDERSON BALLARD BARREN BPilH BELL BOONE BOURBON BOYD BOYLE BRACKEN BRJXBllT BRECKINRIDGE J3~ll-r BUTLER gk?zE gz?iE CARROLL EiF cHRETIAN 80 85 80 85 80 85 85 . ii 85 ii 85 85 80 85 80 85 75 75 75 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70 70
