transportation design manual

7/27/2019 transportation design manual

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FLORIDA DEPARTMENT OF TRANSPORTATION

FDOT MODIFICATIONS TO STANDARD

SPECIFICATIONS FOR STRUCTURAL SUPPORTS

FOR HIGHWAY SIGNS, LUMINAIRES

AND TRAFFIC SIGNALS (LTS-6)

FDOT STRUCTURES MANUAL

VOLUME 9

JANUARY 2013


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FDOT Modifications to LTS-6 Topic No. 625-020-018

January 2013

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Structures Manual Home

Table of Contents

Table of Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 General Features of Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1 Scope (Rev. 01/13) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.4 Functional Requirements (Rev. 01/13) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.4.2 Structural Supports for Signs and Traffic Signals . . . . . . . . . . . . . . . . . . . 1

2.4.2.2 Size, Height and Location of Signs (Rev. 01/13) . . . . . . . . . . . . . . . . . 1

Figure 1 Example: actual signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Figure 2 Example: signs used in design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.4.2.4 Variable Message Signs (Rev. 01/13). . . . . . . . . . . . . . . . . . . . . . . . . . 3

2.4.2.5 Horizontal Span and Cantilever Limits . . . . . . . . . . . . . . . . . . . . . . . . . 3

3 Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.8 Wind Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.8.2 Basic Wind Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.8.3 Wind Importance Factor Ir(Rev. 01/13). . . . . . . . . . . . . . . . . . . . . . . . . . . 4

FDOT Table 3-3 Minimum Design Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.8.6 Drag Coefficients Cd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.8.7 Lift Coefficient for Traffic Signals Cl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.9 Design Wind Loads On Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.9.1 Load Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.9.3 Design Loads for Vertical Supports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53.10 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5 Steel Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.5 Material - Structural Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.13 Cables And Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.14 Details of Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.14.3 Transverse Plate Thickness (Rev. 01/13) . . . . . . . . . . . . . . . . . . . . . . . . 6

5.15 Welded Connections (Rev. 01/13) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.15.1 Tube-to-Tube Splice Circumferential Welds (Rev. 01/13) . . . . . . . . . . . . 7

5.15.3 Tube-to-Transverse Plate Connection Welds (Rev. 01/13) . . . . . . . . . . . 75.16 Bolted Connections (Rev. 01/13) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5.17 Anchor Bolt Connections (Rev. 01/13) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5.17.1 Anchor Bolt Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

5.17.2 Anchor Bolt Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

5.17.3 Design Basis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

5.17.3.3 Use of Grout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
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1 INTRODUCTION

C 1.1Add the following:Structures Manual Introduc t ionI.6 is

updated annually to reflect the specificspecifications editions and interimsadopted by the FDOT.

1.1 Scope

Add the following:

Conform to the date specific AASHTOPublications listed in Structures ManualIntroduct ionI.6 References.

2 GENERAL FEATURES OF DESIGN

C 2.1Add the following:The FDOT Plans Preparation Manualcontains additional FDOT requirements forsign, signal and lighting structures. The

FDOT Design Standardscontainsdrawings for all typical sign, signal andlighting structures.

2.1 Scope (Rev. 01/13)

Add the following:

See Chapters 2, 7 and 29 of the FDOTPlans Preparation Manual, Volume 1

regarding the use of FDOT DesignStandards and other plans preparationrequirements.

2.4 Functional Requirements(Rev. 01/13)

2.4.2 Structural Supports for Signsand Traffic Signals

C 2.4.2.2Add the following:Minimum sign areas provide a reasonableallowance for future sign panelinstallations without the need for a newsupport structure.Minimum sign areas for overhead variablemessage sign supports are normally notrequired.

See the FDOTPPM, Volume 1,Introduction for a link to the Urban AreaBoundary Maps. See PPM, Volume 1 forcantilever and span overhead sign supportlocation criteria.

2.4.2.2 Size, Height and Location ofSigns (Rev. 01/13)

Add the following:

Span type overhead sign structures inurban locations shall be designed eitherfor the actual signs shown on the signingplans or for a minimum sign area of 120sq. ft. (12 ft. W x 10 ft. H) per lane,whichever is the greater. If the signingplans require signs for only one trafficdirection, the minimum sign area per lanerequirement applies to the traffic lanes in

this direction only.

Cantilever type overhead sign structuresin urban locations shall be designed eitherfor the actual signs shown on the signingplans or for a minimum sign area of 80 sq.ft. (8 ft. W x 10 ft. H) located at the end ofthe cantilever, whichever provides the
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more stringent load or stress at thelocation under consideration.

Figures 1 and 2 show how to apply theabove minimum sign areas for span typeoverhead sign structures in urban

locations.Overhead signs in rural locations shouldbe designed for the actual sign shown onthe signing plans.

Figure 1 Example: actual signs

Figure 2 Example: signs used in design
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C 2.4.2.4Add the following:The minimum requirements given provideadditional measures to limit the possibilityof galloping.

Since cantilever overhead VariableMessage Sign (VMS) structures are moresusceptible to fatigue than span overheadVMS structures, span structures should beused whenever possible.

In Florida, overhead VMS structures aretypically referred to as Dynamic MessageSign (DMS) structures.

2.4.2.4 Variable Message Signs(Rev. 01/13)

Add the following:

For all overhead Variable Message Sign(VMS) structures, the horizontal membershall consist of a truss with a minimum oftwo chords with a minimum center-to-center distance between the chords of 3'-0". See FDOT section 11.8 for VMSmaximum span-to-depth ratios.

FDOT vertical clearance requirements forVMS structures are found in PPM, Volume1, Chapter 2.

C 2.4.2.5

Add the following:These limits were chosen based on pastpractice and practical experience.

A FDOT Design Variation is required whensign or signal structure limits areexceeded. The design variationdocumentation shall include the type ofstructure, height, length, discussion ofalternatives, and costs.

2.4.2.5 Horizontal Span and CantileverLimits

New Section, add the following:

Sign and signal structures shall be limited tothe following maximum horizontal lengths:

Structure Type Max Length

Span Overhead Sign 250 feet

Cantilever Overhead Sign 50 feet

Mast Arm 78 feet

Span Wire Assembly 250 feet

3 LOADS

C 3.8FDOTPPM, Volume 1, Section 25.4.27defines the structures where evaluation isnecessary.

3.8 Wind Load

Delete the last paragraph and add thefollowing:

The use of Appendix C is only permittedfor the evaluation of existing structures.

C 3.8.2Add the following:FDOT SDGTable 2.4.1-2was derivedfrom the ASCE 7-05 wind speed map.

To simplify the design process, FDOT hasdesignated one wind speed per county.

3.8.2 Basic Wind Speed

Delete the entire paragraph includingFigure 3-2, and add the following:

The wind loads shall be based on the windspeeds (mph) shown in FDOT SDGTable2.4.1-2
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C 3.8.3Add the following:A 1.5-year design life has been added fortemporary construction signs. Theimportance factor is calculated based on"Wind Speed for Design of TemporaryStructures" by D.W. Boggs and J.A.Peterka, Structures Congress, 1992,Compact Papers, ASCE, 1992.

Florida has traditionally designedLuminaire support structures, 50 feet inheight and less, and strain poles for a 25year design life.

Concrete strain poles are designed for

zero tension stress, therefore a twenty-fiveyear design life is appropriate.

3.8.3 Wind Importance FactorIr(Rev. 01/13)

Add the following Wind Importance Factor

to Table 3-2:

RecurrenceInterval

Years

V =85-100

mph

V > 100

mphAlaska

1.5 0.45 0.2 ---

Delete Table 3-3 and add the followingFDOT Table 3-3:

FDOT Table 3-3 Minimum Design Life

Design Life Structure Type

50-year

Overhead sign structures

Luminaire support structures>50' in height.

Mast Arms

Monotubes

Steel Strain Poles

ITS Camera Poles >50 in

height

25-year

Luminaire supports and other

structures 50' in height.

Concrete Strain Poles

10-year Roadside sign structures

1.5-year Temporary construction signsA 1.5-year design life (Ir= 0.2) for

temporary construction signs shall only beused with a 150 mph design wind speed.

C 3.8.6Add the following to note 2 at the bottomof Table 3-6:

A drag coefficient for traffic signal installedwith the ability to swing has beenestablished through research (Cook

2007). On span wire systems where signaland signs are allowed to swing, varying Cd

as a function of swing angle is allowed(Hoit and Cook 1997).

3.8.6 Drag Coefficients Cd

Replace the coefficient of drag for TrafficSignals in Table 3-6 with the following:

Traffic Signals - no ability to swing - 1.2

Traffic Signals - installed with the ability toswing on span wire systems under fullwind load - 0.7


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3.10 References

Add the following:

Cook, R.A. (2007). Development ofHurr icane Resistant Cable Supp orted

Traff ic Sign als(FDOT Report# BD545RPWO #57). Gainesville, Florida:University of Florida.

Hoit, M.I., Cook, R.A. (1997). ComputerAided Design Program fo r Signal Pole

and Span Wire Assemb l ies With Two

Point Connect ion System(FDOTReport# 0510653). Gainesville, Florida:University of Florida.

5 STEEL DESIGN

C 5.4Add the following:In some environmental conditions inFlorida, A588 steel has deterioratedsignificantly faster than expected.

5.5 Material - Structural Steel

Add the following:

Do not specify ASTM A588 (rustic, Corten,self-oxidizing", or "self-weathering") steelin sign, signal, or lighting structures.

C 5.13Add the followingCables used in the construction of span-

wire pole structures are listed in FDOTSpecification 634.

5.13Cables And Connections

Add the following:

Use the cable breaking strength valuesspecified in FDOT Specification 634.

5.14 Details of Design

C 5.14.3Add the following:Research has proven full-penetrationgroove welds combined with thicker baseplates increases the pole-to-base-plateconnection fatigue strength.

5.14.3 Transverse Plate Thickness(Rev. 01/13)

Add the following:

For base plate connections withoutstiffeners on 50 year recurrence interval

structures, the minimum base platethickness shall be 2 inches.

C 5.15Add the following:Section 5.15 is referenced as a requirementin FDOT Specification 460-6.4.

5.15 Welded Connections (Rev. 01/13)


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C 5.15.1Add the following:The Departments intent is to avoid anyunnecessary welds on sign, signal orlighting structures.

5.15.1 Tube-to-Tube SpliceCircumferential Welds(Rev. 01/13)

Add the following:

On steel sign and signal structures, nocircumferential welds are permitted on theuprights, arms or chords with theexceptions of the base plate weld, theflange plate connections on tubular trussmembers, mitered arm-to-upright angleweld on monotubes. and uprights greaterthan 40 feet in height.

C 5.15.3Add the following:Research has proven full-penetrationgroove welds combined with thicker baseplates increases the pole-to-base-plateconnection fatigue strength.

5.15.3 Tube-to-Transverse PlateConnection Welds (Rev. 01/13)

Add the following:

For base plate connections withoutstiffeners on 50 year recurrence intervalstructures, only use full-penetrationgroove welds.

C 5.16Add the following:Through bolted connections provide fullytensioned A325 bolts.

5.16 Bolted Connections (Rev. 01/13)

Add the following:

Design all pole to arm connections onMast Arm structures as "through bolted".Tapped connections are not permitted. Donot use hardened steel washers betweenthe end plate of a Mast Arm and themounting plate of the pole.

C 5.17Add the following:A minimum of eight anchor bolts providesredundancy and better distribution offorces through the base plate.

5.17 Anchor Bolt Connections(Rev. 01/13)

Add the following:

All sign, signal, and lighting structuresdesigned for a minimum service life of 50years (wind speed based on a 50-yearmean recurrence interval) shall use aminimum of eight, Grade 55, ASTM F1554anchor bolts at the pole to foundationconnection, with the exception of Mast

Arm signal structures where the minimumis six anchor bolts.


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6 ALUMINUM DESIGN

C 6.1Add the following:Aluminum overhead sign structures have

been prone to unacceptable levels ofvibration and fatigue cracking.

6.1 Scope

Add the following:

Do not specify aluminum overhead signstructure supports with the exception ofthe vertical sign panel hangers, which maybe aluminum or steel.

7 PRESTRESSED CONCRETE

DESIGN

7.5 Design

C 7.5.1Add the following:

FDOT uses Standard Prestressed ConcretePoles in accordance with Index 17725 andSpecification 641. After analysis of the

proposed span-wire pole structure, theDesigner selects the appropriate pole usingthe design moment values given in theInstructions for Design Standards for Index17725.

7.5.1 Method of Design

Add the following:

For Standard Prestressed Concrete PoleDesign, see Instructions for DesignStandard Index 17725, for the ServiceMoment Capacity and Ultimate Moment

Capacity. An increased percentage ofAllowable Stress for Group II loading (LTSTable 3-1) is not applicable for PrestressedConcrete Poles, since Group II loading is anultimate moment capacity calculation.

C 7.5.2Add the following:FDOT uses Class V Special, 6 ksi or ClassVI 8.5 ksi concrete in accordance withSpecification 346.

7.5.2 Concrete Strength

Replace this section with the following:

The minimum compressive concretestrength shall be 6 ksi.

7.10 Durability

C 7.10.2Add the following:FDOT requires a minimum 1 inch cover onall concrete poles in all environments.

7.10.2 Concrete Cover


The minimum clear concrete cover for allprestressed and non-prestressed poles is1 inch.


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10 SERVICEABILITY

REQUIREMENTS

C 10.5Add the following:Permanent camber equal to 1.5 times thedead load deflection provides for a better

appearance than the relatively small L/1000given in AASHTO. For mast arms, a twodegree upward angle at the arm/uprightconnection is standard industry practice.

10.5Camber


Provide permanent camber equal to 1.5times the dead load deflection for overheadsign structures. For span overhead signstructures, arch the horizontal memberupwards and for cantilever overhead signstructures rake the vertical supportbackwards. For mast arm signal structures,provide a two degree upward angle at thearm/upright connection.

11 FATIGUE DESIGN (Rev. 01/13)

C 11.6Add the following:Research performed at the University ofTexas (Report 0-4178) concludedincreasing "the end plate thickness for a10-inch mast arm from 1.5 inches to 2inches increased the fatigue life fromcategory E' to category D."

Since FDOT Design Standards andprograms for Mast Arm signal structures,overhead tri-chord sign trusses, and High-mast light poles use relatively thick baseplates, Fatigue Category II is appropriate.In addition, there have been no reports offatigue damage to sign, signal and lightingstructure designed using FDOT programsand built using FDOT Design Standards.

11.6 Fatigue Importance Factors(Rev. 01/13)

Add the following:

Use Fatigue Category II for all flat panelsign, traffic signal, and lighting supportstructures meeting the limits in 2.4.2.5 anddesigned using FDOT Design Standardsand Programs or designed in accordancewith Chapter 4 of NCHRP W176, "Cost-Effective Connection Details for HighwaySign, Luminaire, and Traffic SignalStructures". Use Fatigue Category I for allother sign, traffic signal, and lightingsupport structure designs including allVMS support structures.


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11.7 Fatigue Design Loads

C 11.7.1Add the following:Vibration mitigation devices are seldomnecessary and installed only afterexcessive vibration has been observed andthe device is approved by the Department.Cantilevered sign support structures withhorizontal three or four chord trusses havenever been reported to vibrate from vortexshedding or galloping. (ref. FHWAGuidelines for the Installation, Inspection,Maintenance and Repair of StructuralSupports for Highway Signs, Luminaries,

and Traffic Signals)

11.7.1 Galloping

Replace the 2nd, 3rd and 4th paragraphswith the following:

Vibration Mitigation devices are notallowed in lieu of designing for galloping.

Exclude galloping loads for the fatiguedesign of overhead cantilevered sign andVMS support structures with three or fourchord horizontal trusses with bolted web tochord connections.

C 11.8Add the following:The minimum requirements given provideadditional measures to limit the possibilityof galloping

11.8 Deflection

Add the following:

In addition, VMS structures shall also meetthe following maximum span-to-depthratios:

VMS Structure TypeMax.

Span-to-DepthRatio

Overhead SpanStructure

25

Overhead CantileverStructure

9

13 FOUNDATION DESIGN

C 13.6Add the following:For standard drilled shaft details, seeDesign Standard Indexes 11320, 17502,17723 and 17745 for span overhead signstructures, high mast light poles, steelstrain poles, and mast arms respectively.

13.6 Drilled Shafts (Rev. 01/13)

Add the following:

Drilled shafts are the standard foundationtype on high mast light poles, overheadsigns, mast arms and steel strain poles.


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13.6.1 Geotechnical Design

C 13.6.1.1Add the following:FDOT experience has established a safetyfactor of 2 produces conservative designs.

The torsion resistance equation is basedon the theory for the Beta Method (O'Neill

and Reese, 1999). A single fdot factorof 1.5 is used to adjust for the concurrentoverturning and torsional forces and tocompare with past FDOT practice. Sincethe consequence of a torsion soil-structurefailure is usually small, some rotation istypically allowable from the design wind.

Since cantilever overhead sign structurescan have significantly more torsion than aMast Arm, a higher safety factor of 1.3 isappropriate.

For soils with SPT N-values less than 5,consult the Geotechnical Engineer foradditional recommendations.

13.6.1.1 Embedment (Rev. 01/13)

Add the following:

Use a safety factor against overturning of

2 when using the Broms method.For torsion resistance in drilled shaftssupporting Mast Arm signal and cantileveroverhead sign structures, use thefollowing equations:

TuTn

SF tor--------------

Where

Tn DLFsD

2----

D

2----

2

LconcD

3----

+=

Fs vfdot=

v soilL

2---

=

soil( )tan=

Tu = Torsion force on the drilled shaft

Tn = Nominal torsion resistance of the

drilled shaft

SFtor = Safety Factor against torsion

= 1.0 for Mast Arm signal structures= 1.3 for overhead cantilever sign

structures

D = diameter of the drilled shaft

L = length of the drilled shaft

Fs = unit skin friction

v = effective vertical stress at mid-layer

fdot = load transfer ratio where theallowable shaft rotation may exceed 10

degrees= 1.5 for granular soils where SPT N-

values are 15 or greater

= 1.5N value

15---------------------------

for N-values

greater than or equal to 5 and lessthan 15.


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= unit weight of concrete

soil = unit weight of soil = Coefficient of friction between the

shaft and soil

soil =soil friction angleC 13.6.2

Add the following:Using 1% steel is conservative for flexuraldesign in most cases. Additional stirrups inthe top of the shaft provides resistanceagainst shear failure in the top of the shaft.Due to torsion, additional stirrups may berequired in cantilever structures.

13.6.2 Structural Design

Add the following:

Longitudinally reinforce drilled shaftfoundations with a minimum of 1% steel.

At a minimum, place #5 stirrups at 4 inchspacing in the top two feet of shaft. Incantilever structures, design for shearresulting from the torsion loading on theanchor bolt group.

C 13.6.2.1Add the following:FDOT requires six inches of cover toensure durability in drilled shafts.

Concrete consolidation below the anchorbolts becomes more difficult withreinforcement clear spacing less than sixinches.

13.6.2.1 Details (Rev. 01/13)

Replace the second sentence with thefollowing:

A minimum concrete cover of six inchesover steel reinforcement is required.

Add the following:

The minimum diameter for drilled shafts is36 inches. A minimum main reinforcement

clear spacing of six inches is required forproper concrete consolidation. Stirrups in

drilled shafts for sign, signal and lightingstructures are exempt from this spacingrequirement.

13.10 Embedment of Lightly LoadedSmall Poles and Posts

Add the following:

When using the Broms method for groundsign foundation design, use a safety factor

against overturning of 1.3. When using theBroms method for direct burial concretepole foundation design, use a safety factoragainst overturning of 1.5.


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13.11 References

Add the following:

Cook, R.A. (2007). Anchor EmbedmentRequirements for Signal /Sign

Structures(FDOT Report# BD545 RPWO#54). Gainesville, Florida: University ofFlorida.

APPENDIX C

C C.1Add the following:By allowing an overstress factor of 1.4,consistent with previous editions of LTS,properly designed existing structures willbe allowed to remain in place in

accordance with thePPM.

C.1 Alternate Method (Rev. 01/13)

Add the following:

When evaluating existing structures inaccordance with PPM25.4.26, the followingdesign assumptions are permitted:

a. an allowable overstress of 1.4 isallowed for Group II loading.

b. allowances for future loads, FDOT2.4.2.2, is not required.

c. evaluation using Section 11, FatigueDesign, is not required (withoutplanned additional loading only).

d. evaluation of the foundation capacity isnot required (without plannedadditional loading only).

C C.2Add the following:To simplify the design process, FDOT hasdesignated one wind speed per county.

C.2 Wind Load

Delete the 2nd and 3rd sentence and addthe following:

The design wind pressures shall becomputed using the wind pressureformula, Eq. C-1, with the appropriatewind speed shown in FDOT Table C.2-1,Wind Speed by County.
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FDOT Table C.2-1 Wind Speed by County

County (Dist)10

year25

year50

yearCounty (Dist)

10year

25year

50year

Alachua (2) 60 80 90 Lee (1) 80 90 100

Baker (2) 60 80 90 Leon (3) 60 70 80Bay (3) 70 80 90 Levy (2) 70 80 90

Bradford (2) 60 80 90 Liberty (3) 60 80 90

Brevard (5) 80 90 100 Madison (2) 60 70 80

Broward (4) 90 100 110 Manatee (1) 80 90 100

Calhoun (3) 60 80 90 Marion (5) 60 80 90

Charlotte (1) 80 90 100 Martin (4) 80 90 100

Citrus (7) 70 80 90 Miami-Dade (6) 90 100 110

Clay (2) 60 80 90 Monroe (6) 90 100 110

Collier (1) 80 90 100 Nassau (2) 70 80 90Columbia (2) 60 70 80 Okaloosa (3) 70 90 100

DeSoto (1) 70 80 90 Okeechobee (1) 70 80 90

Dixie (2) 70 80 90 Orange (5) 70 80 90

Duval (2) 70 80 90 Osceola (5) 70 80 90

Escambia (3) 70 90 100 Palm Beach (4) 80 100 110

Flagler (5) 70 80 90 Pasco (7) 70 90 100

Franklin (3) 70 90 100 Pinellas (7) 70 90 100

Gadsden (3) 60 70 80 Polk (1) 70 80 90

Gilchrist (2) 60 80 90 Putnam (2) 60 80 90Glades (1) 70 80 90 St. Johns (2) 70 80 90

Gulf (3) 70 90 100 St. Lucie (4) 80 90 100

Hamilton (2) 60 70 80 Santa Rosa (3) 70 90 100

Hardee (1) 70 80 90 Sarasota (1) 80 90 100

Hendry (1) 70 80 90 Seminole (5) 70 80 90

Hernando (7) 70 90 100 Sumter (5) 60 80 90

Highlands (1) 70 80 90 Suwannee (2) 60 70 80

Hillsborough (7) 70 80 90 Taylor (2) 70 80 90

Holmes (3) 60 70 80 Union (2) 60 80 90Indian River (4) 80 90 100 Volusia (5) 80 90 100

Jackson (3) 60 70 80 Wakulla (3) 70 80 90

Jefferson (3) 60 70 80 Walton (3) 70 80 90

Lafayette (2) 60 80 90 Washington (3) 60 80 90

Lake (5) 60 80 90


January 2013

15



19/19


Volume 9 - Revision History January 2013

R9-1


VOLUME 9 - REVISION HISTORY

2.1 ................Added PPM cross reference. Revised Commentary.

2.4 ................Renumbered entire Section.

2.4.2.2 ..........Revised Commentary.

2.4.2.4 ..........Added cross reference for vertical clearance requirements.

3.8.3 .............Revised Table 3-3.

5.14.3 ...........Revised Section title.

5.15 ..............Added Commentary

5.15.1 ...........Revised Section title. Added provision for uprights > 40.

5.15.3 ...........Revised Section title.

5.16 ..............Added limitation for use of hardened steel washers.

5.17 ..............Revised minimum number of anchor bolts.

5.17.4.3 ........Revised Commentary.

11 .................Deleted Sections 11.5 Design Criteria and 11.9 Fatigue Resistance.

11.6 ..............Clarified requirements of Section 11.6.

13.6 ..............Clarified the requirements of Section 13.6.

13.6.1.1 ........Revised variable definition for load transfer ratio. Added fourth Paragraph toCommentary.

13.6.2.1 ........Added clarification for spacing requirement.C.1 ...............Revised cross reference. Added clarification.

Documents

transportation design manual