ANSI - NESC Update

ANSI - NESC UpdateANSI - NESC Update

Nelson G. Bingel IIIChair - ANSI O5Principal - NESC


2005 AWPA Annual Meeting New Orleans, LA May 15 - 18

NESC - SafetyNESC - Safety

ANSI O5 - MaterialANSI O5 - Material

FIBERFIBERSTRESSSTRESS

CLASSCLASSLOADSLOADS

WOODWOODQUALITYQUALITY

POLEPOLEDIMENSIONDIMENSION

SS

LL

c c

DD

2 ft2 ft

Class 1 4,500 Class 1 4,500 lblbClass 2 3,700 Class 2 3,700 lblbClass 3 3,000 Class 3 3,000 lblbClass 4 2,400 Class 4 2,400 lblbClass 5 1,900 Class 5 1,900 lblb

Compression (psi)Tension (psi)

Bending Capacity =Bending Capacity =

kk xx fiber strength fiber strength xx C C33 (ft-lb) (ft-lb)

Fiber StrengthFiber StressModulus of Rupture

ANSI O5.1 ANSI O5.1

Bending Load = LBending Load = Lc c xx D (ft- D (ft-lb)lb)

LL

cc

kk xx fiber strength fiber strength xx C C33 (ft- (ft-lb)lb)

ANSI O5.1 ANSI O5.1

Bending Bending Capacity Capacity

== kk xx fiber strengthfiber strength xx C C33 (ft- (ft-lb)lb)

kk xx fiber strengthfiber strength xx CC33 (ft- (ft-lb)lb)

2002 ANSI O5.1 2002 ANSI O5.1

Changes in Scope

Changes to Table 1, Fiber Stress

Annex A moved into the Standard

Changes in Scope

Changes to Table 1, Fiber Stress

Annex A moved into the Standard

Issued in March 2002Issued in March 2002

Scope Scope

Simple Cantilever Simple Cantilever

Single PoleSingle Pole TransverTransverse se

Scope Scope

Taller Taller PolesPoles TaperTaper

Maximum Stress Point Maximum Stress Point May Occur Above May Occur Above

GroundGroundFiber Stress Fiber Stress Height EffectHeight Effect

Height of Height of Applied LoadsApplied Loads

Table 1 – Fiber StressesTable 1 – Fiber Stresses

Eliminate Species not Used

New Footnote 1• The effects of conditioning on fiber stress have

been accounted for in Table 1 values

New Footnote 2• These designated fiber stresses represent a

mean, groundline, fiber stress value with a COV = .20

Eliminate Species not Used

New Footnote 1• The effects of conditioning on fiber stress have

been accounted for in Table 1 values

New Footnote 2• These designated fiber stresses represent a

mean, groundline, fiber stress value with a COV = .20

#40

Symmetrical Bell Curve Symmetrical Bell Curve DistributionDistribution

COV

8000 psi6400 psi 9600 psi

Scope, Section 9, Table 1 Scope, Section 9, Table 1

Taller Taller PolesPoles TaperTaper

Fiber Stress Fiber Stress Height EffectHeight Effect

Height of Height of Applied LoadsApplied Loads Maximum Stress Point Maximum Stress Point

May Occur Above May Occur Above GroundGround

Mean Fiber Mean Fiber Stress,Stress,

COV, ConditionedCOV, Conditioned

Net Result of ChangesNet Result of Changes

Distribution – Little Distribution – Little ChangeChange

Transmission – Maybe Larger Transmission – Maybe Larger PolesPoles

Conservative

ANSI Task Force - 2004• Todd Brown

• Martin Rollins

• Nelson Bingel

• Stephen Smith

• Bob Reisdorff

ANSI Task Force - 2004• Todd Brown

• Martin Rollins

• Nelson Bingel

• Stephen Smith

• Bob Reisdorff

Pole Dimension Data CollectionPole Dimension Data Collection

• Martin Rollins• Martin Rollins

• Todd Brown• Todd Brown

?

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?

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TX

MO

MN

LA

OK

I A

KS

AR

NE

SD

ND

Sample Locations

Coastal Douglas Fir (8)

Coastal DF & Western Red (3)

Northern Red Pine (3)

Southern Yellow Pine (16)

Western Red Cedar (5)

ANSI Dimension Data CollectionANSI Dimension Data Collection

Coastal Douglas fir 6,185 poles• 9 Producers; 11 Locations

Southern Yellow Pine 5,429 poles• 11 Producers; 16 Locations

Western Red Cedar 5,701 poles• 5 Producers; 9 Locations

Northern Red Pine 2,122 poles• 2 Producers; 3 Locations

Coastal Douglas fir 6,185 poles• 9 Producers; 11 Locations

Southern Yellow Pine 5,429 poles• 11 Producers; 16 Locations

Western Red Cedar 5,701 poles• 5 Producers; 9 Locations

Northern Red Pine 2,122 poles• 2 Producers; 3 Locations


Grand Total 19,527 poles

Oversize at

Guy Attachments

Oversize at

Guy Attachments


>Class OversizeClass Oversize

++

Fiber Stress Fiber Stress Height ReductionHeight Reduction

Change ProposalsChange Proposals 1 Scope and general requirements

• Remove design considerations from 1.1 Scope

• Create 1.3 Design Considerations

• Explain maximum stress point more clearly

• State that fiber stress height reduction need not apply to poles 55 feet and shorter

• State that fiber stress height reduction need not apply to braced H-frames due to load sharing

1 Scope and general requirements

• Remove design considerations from 1.1 Scope

• Create 1.3 Design Considerations

• Explain maximum stress point more clearly

• State that fiber stress height reduction need not apply to poles 55 feet and shorter

• State that fiber stress height reduction need not apply to braced H-frames due to load sharing

Change Proposals cont’dChange Proposals cont’d

Section 9 Fiber stress height effect

• Modify to apply only to poles 60 feet and taller

Section 6.2.1

• Add to the end of the first sentence:o “after bark removal and /or shaving”

Section 9 Fiber stress height effect

• Modify to apply only to poles 60 feet and taller

Section 6.2.1

• Add to the end of the first sentence:o “after bark removal and /or shaving”

Photo ManualPhoto Manual

Tropical Hardwood PolesTropical Hardwood Poles

Amazon Region in BrazilAmazon Region in Brazil

Tropical Hardwood PolesTropical Hardwood Poles

Task Force to Review Test Data• David D’Hooge• Bob Kluge• Art Peralta• Gina Cerda• Martin Rollins• Jeff Morrell

Nelson Bingel to coordinate the effort

Task Force to Review Test Data• David D’Hooge• Bob Kluge• Art Peralta• Gina Cerda• Martin Rollins• Jeff Morrell

Nelson Bingel to coordinate the effort

Tropical Hardwood CrossarmsTropical Hardwood Crossarms

OSU Through-Boring ProjectOSU Through-Boring Project

Computer Finite Element Analysis

Compare impact on pole strength• Hole size• Hole spacing• Hole distance from pole edge

Test Procedure

Build Test Stand

Obtain Poles

Pole Testing

Computer Finite Element Analysis

Compare impact on pole strength• Hole size• Hole spacing• Hole distance from pole edge

Test Procedure

Build Test Stand

Obtain Poles

Pole Testing

OSU Through-Boring ProjectOSU Through-Boring Project

Industry Standard Drilling Pattern

Understanding of Strength Impact• Coordinate with ANSI O5

ANSI O5 to coordinate with AWPA • Review treatment effectiveness

Industry Standard Drilling Pattern

Understanding of Strength Impact• Coordinate with ANSI O5

ANSI O5 to coordinate with AWPA • Review treatment effectiveness

OSU Through-Boring Project OSU Through-Boring Project

Results / Additional Standard Activity

CP 2737 – Major RevisionCP 2737 – Major Revision

Conditionally Accepted

Pending Results of Task Force 5.2.1

Some Concepts

• New Ice & Wind Map – ASCE 7

• Apply Extreme Wind to all Structures

• Include .87 Grade C Strength Factor

• Grade B / C differential @ 1.5

Conditionally Accepted

Pending Results of Task Force 5.2.1

Some Concepts

• New Ice & Wind Map – ASCE 7

• Apply Extreme Wind to all Structures

• Include .87 Grade C Strength Factor

• Grade B / C differential @ 1.5

60 ft Exclusion Limit60 ft Exclusion Limit Eliminate exclusion but calibrate to previous

practice.

Only partially accomplished

Increase in Medium Loading District

Requires utilities to consider additional load case

Eliminate exclusion but calibrate to previous practice.

Only partially accomplished

Increase in Medium Loading District

Requires utilities to consider additional load case

Incorporate 2002 ANSI O5.1Incorporate 2002 ANSI O5.1

Rule 261 A2b(1)• Include reference to “fiber stress height

effect”

Rule 261 A2b(1)• Include reference to “fiber stress height

effect”

b. Permitted Stress Level(1)Natural Wood PoleThe permitted stress level of natural grown wood poles of various species meeting the requirements of ANSI O5.1-2002 shall be determined by multiplying the designated fiber stress (recognizing the “fiber stress height effect” as appropriate) set forth in that standard by the appropriate strength factors in Table 2610-1A or 261-1B.

Incorporate 2002 ANSI O5.1Incorporate 2002 ANSI O5.1

Rule 261 A2b(1)• Include reference to fiber stress height

effect Rule 261 A2a exception 1

• Delete because of reference to allowable groundline stress

Rule 261 A2b(1)• Include reference to fiber stress height

effect Rule 261 A2a exception 1

• Delete because of reference to allowable groundline stress

EXCEPTION 1: When installed, naturally grown wood poles acting as single-based structures or unbraced multiple-pole structures, shall meet the requirements of Rule 261A2a without exceeding the permitted stress level at the ground line for unguyed poles or at the points of attachment for guyed poles.

Introduce ASCE RBD ManualIntroduce ASCE RBD Manual

Three variations submitted• Refer to the manual• 2 new rules including the manuals• Major rewrite incorporating the manual

All Rejected• Manual only addresses single, un-guyed• Not a consensus document• Several “To Be Determined” values

Three variations submitted• Refer to the manual• 2 new rules including the manuals• Major rewrite incorporating the manual

All Rejected• Manual only addresses single, un-guyed• Not a consensus document• Several “To Be Determined” values

Introduce FRP StructuresIntroduce FRP Structures Accepted

• Several Rules affected

• Same Strength & Load Factors as Metal

• 5% LEL Strength Established by Manufacturers

Accepted

• Several Rules affected

• Same Strength & Load Factors as Metal

• 5% LEL Strength Established by Manufacturers

Grade B Grade C

Strength factors for use with loads of Rule 250B

Metal and Prestressed-Concrete Structures 6 1.0 1.0

Wood and Reinforced-Concrete Structures 2,4 0.65 0.85

Fiber-Reinforced Polymer Structures 6 1.0 1.0

Support Hardware 1.0 1.0

Guy Wire 5,6 0.9 0.9

Guy Anchor and Foundation 6 1.0 1.0

Strength factors for use with loads of Rule 250C

Metal and Prestressed-Concrete Structures 6 1.0 1.0

Wood and Reinforced-Concrete Structures 3,4 0.75 0.75

Fiber-Reinforced Polymer Structures 6 1.0 1.0

Support Hardware 1.0 1.0

Guy Wire 5,6 0.9 0.9

Guy Anchor and Foundation 6 1.0 1.0

Table 261-1AStrength Factors for Structures, Crossarms, Support Hardware,

Guys, Foundations, and Anchors for Use with Overload Factors of Table 253-1

Average Strength of 3 PolesAverage Strength of 3 Poles Accepted to Delete this Rule Accepted to Delete this Rule

Delete Alternate OL for WoodDelete Alternate OL for Wood Accepted – Delete Table 253-2 Accepted – Delete Table 253-2

ANSI - NESC UpdateANSI - NESC Update



2005 AWPA Annual Meeting New Orleans, LA May 15 - 18

Documents

ANSI - NESC Update