bruce peterson handout 6 per page.pdf

8/20/2019 Bruce Peterson handout 6 per page.pdf

1/36

The Rehabilitation AlternativeHuey P. Long Bridge Case Study

Bruce E. Peterson, P.E.Project Manager

Modjeski and Masters, Inc.

March 22, 2010

Introduction• Replacement vs. Rehabilitation

• Project Background

• 4 Construction Contracts – Main Bridge – Substructure – Main Bridge – Superstructure

Truss Widening – Railroad Modifications – Approaches and Main Bridge

Deck Widening

BREAK

• Project Status – Project Timeline – Construction Photographs

EXISTING

PROPOSED WIDENING

Replacement vs. RehabilitationBridge construction represents a large capital investment.

Through time, all bridges receive “routine maintenance”.However, eventually they must be replaced or rehabilitated.

Beyond the obvious difference in cost, there are othersignificant differences between these two approaches.

How is the decision made?

What influences the choice between these two alternatives?

Replacement vs. RehabilitationLouisiana Dept. of Transportation and Development

(LADOTD)

Methodology for Selecting and Programming Bri dges forReplacement and Rehabilitation

Priority for the selection of bridges for replacement orrehabilitation with Federal bridge replacement funds basedon three (3) parameters:

1. Structural adequacy

2. Functional adequacy and serviceability

3. Essential for public use

Replacement vs. RehabilitationThe three parameters are based on the following information:

1. Structural deficiency

2. Posted bridges (weight limits below statutory limits)

3. Traffic count (ADT)

4. Class of highway

5. Available detour routes

6. Bridge geometry (particularly bridges < 20 ft. wide)

7. Bridge inspection reports

8. Local district recommendations for replacement(submitted annually)

Replacement vs. RehabilitationFederal Highway Administration (FHWA) formula for prioritizing

bridges

Overall rating called a “sufficiency rating”

Sufficiency rating assigns a numeric value ranging from 0 to

100 to a given bridge with the following percentage pointsapplied to each parameter

ITEM WEIGHT

Structural Adequacy 55 %

Functional Adequacy andServiceability 30 %

Essential For Public Use 15 %


2/36

Replacement vs. RehabilitationRequirement f or replacement:

• Sufficiency Rating < 50

• Classification as structurally deficient or functionallyobsolete

Requirement for rehabilitation:

• Sufficiency Rating < 80

Replacement vs. Rehabilitation As previously noted there are three elements to the Sufficiency

Rating

1. Structural Adequacy2. Functional Adequacy and Serviceability

3. Essential for Public Use

Let’s examine each in detail.

Replacement vs. RehabilitationStructural Adequacy

Most important factor in evaluation process as a bridge failurecould be catastrophic

Determined from:

• List of posted bridges (bridges with load restrictions)

• Bridge inspection reports

• Local district recommendations

Replacement vs. RehabilitationFunctional Adequacy and Serviceability

Bridge geometry a key element

• Clear roadway width most important factor

• Narrow bridges, if structurally adequate, can be widenedrather than replaced

Determined from:

• Bridge inspection reports

• Local district recommendations

Replacement vs. RehabilitationFunctional Adequacy and Serviceability (con’d)

Serviceability is related to factors such as

• Stream scour

• Maintenance for movable bridges

• Deck deterioration

Other important factors include frequency and severity ofmarine, railroad, and automotive traffic accidents

Replacement vs. RehabilitationEssential For Public Use

Determined by the:

• Traffic count (ADT)

• Class of highway

• Available detour routes

Structural and functional adequacy of the bridge is evaluatedwith the traffic count in order to minimize exposure tounsafe conditions

Example: two bridges with the same degree ofinadequacy, the one with the higher traffic volumewould receive the higher priority


3/36

Replacement vs. RehabilitationEssential For Public Use (con’d)

Bridges located on a truck or school bus route or crosses a

major river or stream receive extra attentionNon-redundant routes (no available detours) receive a higher

priority than bridges on redundant routes

Replacement vs. RehabilitationHow Select?

Numerous rational methods available

Recommended procedure for State of Louisiana1. Compile 3 lists

• Bridges with lowest sufficiency rating

• Bridges with the highest priority based on local districtrecommendations

• Bridges that are most severely posted for loadrestrictions

2. Generally, if a bridge makes all three lists, it will have a highpriority for replacement

Replacement vs. RehabilitationSTRUCTURAL

ADEQUACY

FUNCTIONAL

ADEQUACY AND

SERVICEABILITY

ESSENTIALLITY

TO THE PUBLIC

Sufficiency Rating

Sufficiency Rating

Sufficiency Rating

Posted Bridges List

Bridge Geometry,

Acci dents , etc.

Highway Class and

Traffic Count (ADT)

Bridge Inspection Report

District Recommendations

Bridge Inspection Report


Avail able Detou r Rout es


FINAL ORDER

OF PRIORITY

Traffic Type

Source: LADOTD Bridge Design Manual

Replacement vs. RehabilitationOther Considerations - ReplacementPros :

1. New structure would meet all currentstandards

• Loads

• Geomet ry

• Highway standards

2. New Construction

• Do not have to connect newcomponents with existing ones.

• Reduced potential for“surprises” during construction

3. Estimating construction costpotentially more accurate

Cons :

1. Potential for greater environmentalimpacts

2. Potential for greater costs

3. Potential need for more right-of-way

4. Can require time for public to agree ona location and other impacts related toa new structure

5. Can take more time from start ofplanning to final completion anddelivery to public

6. Removal of an historic structure

Replacement vs. RehabilitationOther Considerations - RehabilitationPros :

1. Have the potential to reuse existingelements, thus saving time andmoney

2. Potentially less environmentalimpacts

3. Potentially less right-of-wayrequirements

4. Can fix some “legacy issues” that donot meet current standards or areless than desirable

Cons :

1. Increased potential for problems andunknown discoveries with the existingstructure

2. Greater demands on determination ofexisting conditions, details, geometry,etc. in order to produce accurate plans

3. Ability to meet all current standardsmay be difficult

4. Accurate estimation of constructioncosts can be difficult

5. Modification of an historic structure

Replacement vs. RehabilitationOther Considerations (con’d)

Environmental

• Historic structure?

• Impacts?

Remaining life of structure

• Structural condition (corrosion) and capacity

• Remaining fatigue life


4/36

Replacement vs. RehabilitationOther Considerations (con’d )

Owner’s Concerns and Issues

1. Time required to perform the work2. Funding

• Available local funding?

• Federal funds available?

3. Public• Wants the work completed “yesterday”

• Does not want to be inconvenienced during the work

• Low cost (no increased direct costs; e.g.. taxes, tolls, etc.)

• While doing this work, why not fix these other problems and/oraddress other needs.... ”it’s only a little more $$” (scope creep)

Replacement vs. RehabilitationWhere does the Huey P. Long Bridge fit within this

criteria?

Structurally Adequacy? - GOOD• Excellent condition; adequate strength

• Reduced fatigue life of stringers and floorbeam brackets

Functionally Adequacy and Serviceability? - POOR• 18 feet wide roadways

• Barriers not current standards

Essential For Public Use? - ESSENTIAL• Few Mississippi River crossings in metro region; essential for

highway traffic

• Only rail crossing of Miss. River south of Baton Rouge

Location

FrenchQuarter

Huey P. Long Bridge

New Orleans Metro Area

Before the Bridge

Before the Bridge Construction of The Existing Bridge


5/36

Construction of The Existing Bridge Construction of The Existing Bridge

Construction of The Existing Bridge Construction of The Existing Bridge

Construction of The Existing Bridge Background – Huey P. Long Bridge

• Completed in December 1935, the bridge isone of the longest railroad bridges in the world.


6/36

Background – Huey P. Long Bridge

• Combinedrailroad – highwaybridge

– 2 tracks

– 4 lanes – 9 ft.width

Background – Huey P. Long Bridge

• Very heavilybuilt• Carries largest

modern RRload withoutdistress

• Many years ofservice liferemaining

Project Background

• By widening the existingstructure rather thanconstructing a new rivercrossing: – Reduce environmental

impact, property takings. – Reduce project cost. – Reuse existing right-of-

way and traffic corridors.

• Final report published April 1988.

Project Background

EXISTING PROPOSED WIDENING

Project Background

1982Study of new bridge in corridor; 5 alternates considered.High cost and large amount of ROW; project dropped.

1986LADOTD authorized M&M to perform conceptual widening study.3 widening alternates considered.

1990 Geotechnical investigation of soil capacity under caissons.

1992-1996

Preliminary Design Main Bridge; Fatigue Evaluation.Line and Grade Study Approaches.

1999-2000

Environmental Processing Agency Consensus

2000-2007

Completion of final design plans; main bridge widening, railroadmodifications, and approaches,

2006-Present

Construction main bridge substructure widening, railroadmodifications, and main bridge superstructure widening.

START PROJECT

END PROJECT

WEST BANK APPR.

WEST BANK RR MOD

EAST BANK RR MOD

EAST BANK APPR.

MAIN BRIDGE PIER, TRUSS, ANDDECK WIDENING

Huey P. Long Widening Project


7/36

START PROJECT

END PROJECT

WEST BANK APPR.

WEST BANK RR MOD

EAST BANK RR MOD

EAST BANK APPR.


Main Bridge Pier Widening Main Bridge Pier Widening

Pier A Piers I & II Pier III Pier IV

EXISTING

PROPOSED WIDENING

Widened Pier

Caisson

SteelFrame

LowerEncase

UpperEncase

Widened Pier - Details

• The steel frame significantly reduces the loads onthe pier by eliminating concrete and permits thecenter bearing to be jacked, relieving load from theexterior bearings.

• This is beneficial by reducing load on the end facesof the existing concrete distribution block on top ofthe existing caisson.

• The upper portion ofthe pier widening iscomposed of a steelframe.


• Inspection access will be provided for the steel metalworkin the upper portion of the pier widening.

• The steel frame willalso permit moreaccurate setting andadjustment of the finalbearing elevations after

the lower encasementis poured.


Constructability of Pier Frame• Must be constructed around existing pier • No construction access from above due to

existing superstructure• Staged construction• Key splice locations.


8/36

Widened Pier - DetailsThe lower portion of the

encasement serves

several functions• The nose areas arecolumns to support thewidening truss supportbearings.

• The remainder confines the existing pier concreteand granite masonry blocks which currently hasminimal reinforcing.


Widened Pier - Details Strength of the Existing Concrete• One of the major questions for widening the

substructure was the strength of the existingconcrete.

• Existing concrete was specified for 2000 psi.• Based on construction records, actual strength

much higher • Using methods to estimate moderate amount of

additional concrete strengthening with aging,4000 psi could be used with confidence for thestrength of the existing concrete.

Strength of the Existing Concrete

PIER AND CAISSON CONCRETE STRENGTHS

LOCATION 1930 2000 - 1 2000 - 2 USED

Piers 3,800 4,500 8,800 4,000

Caisson 3,300 3,870 7,565 3,800

2000-1 = ACI Committee 209, “Prediction of Creep, Shrinkage, andTemperature Effects in Concrete Structures” (ACI 209R-92)

2000-2 = Properties of Concrete” by A. M. Neville

Existing Pier ConditionsUnderwater Acoustic Inspection performed April 2006 by C.

H. Fenstermaker & Associates.

Piers I, II, III, & IV examined and found to be in goodcondition.

The equipment provided detailed information of the existingconditions.

Examination though the use of a diver would be more costly,must be performed in extreme low to no visibility, and isdangerous.


9/36

Existing Pier Conditions

Pier I – North Face

Existing Pier Conditions

Pier II – West Nose

START PROJECT

END PROJECT

WEST BANK APPR.

WEST BANK RR MOD

EAST BANK RR MOD

EAST BANK APPR.

MAIN BRIDGE PIER, TRUSS, AND

DECK WIDENING

Main Bridge Truss Widening Main Bridge Truss Widening

Cantilever Truss Span

SimpleThrough

Truss Span EXISTING

PROPOSED WIDENING

Cross Sections – Existing Bridge

• 2 new trusses added, parallelto existing trusses.

• Roadways widened from 18ft. to 43 ft.

• Currently: 2 – 9 ft. lanesNo offset

• Proposed: 3 – 11 ft.lanes

8 ft. shoulder 2 ft. offset

Widened Main Bridge Features


10/36

Nomenclature• Normal terminology

for truss bridges

would be U.S. & D.S.trusses.• Widened HPL Bridge

is a multiple trussplane structure – U.S. Widening Truss – U.S. Existing Truss – D.S. Existing Truss – D.S. Widening Truss

2D versus 3D Analysis and DesignTraditional Truss Analysi s (2D)• Vertical loads, e.g. D & L, supported by main (vertical)

trusses• Transverse loads, e.g. W, supported by top and bottom

lateral trusses, sway frames, and portals

3 Dimensional Analysis Used• Widened bridge is multiple truss plane

system• 3D analysis reflects the reality of the

structure and its behavior • Load sharing will occur and it is beneficial• Members not normally supporting live load

will have live loads• Need to know the amount of live load in

non-traditional live load supportingmembers.

2D versus 3D Analysis and Design 2D versus 3D Analysis and Design

3D SAP Computer Model

Floorbeam and Hangers• Superposition needed to

solve final forces in theexisting and widenedhangers

• Moment and sequence ofconstruction affect forces

Construction and Erection

• Method and Sequenceof Constructionprovided in ContractPlans

• Contractor proposedoption also available incontract plans

• Contractor proposedhis own method


11/36

Maintenance of Traffic Through Construction

• Marine Traffic Maintained – same vertical and horizontal

clearances

• Rail Traffic Maintained

• Vehicular Traffic Maintained – by use of staged construction

Main BridgeMaintenance of Traffic

WORK PERFORMED INTRUSS WIDENING

CONTRACT

Main BridgeMaintenance of Traffic - Stage 1

WORK PERFORMED INTRUSS WIDENINGCONTRACT


PREVIOUS STAGE

WORK PERFORMED INTRUSS WIDENINGCONTRACT


PREVIOUS STAGE

WORK PERFORMED INTRUSS WIDENING

CONTRACT


PREVIOUS STAGE

WORK PERFORMED IN APPROACH AND DECKWIDENING CONTRACT


12/36

Main BridgeMaintenance of Traffic - Stage 4 - 5

SWITCH TRAFFIC


PREVIOUS STAGE



PREVIOUS STAGE



PREVIOUS STAGE


• Top laterals, bottomlaterals, swayframes, and portalframes must hinge

to permit movement• Erect rigid part overroadways open totraffic; hingeremaining part.

Deflection Issues

START PROJECT

END PROJECT

WEST BANK APPR.

WEST BANK RR MOD

EAST BANK RR MOD

EAST BANK APPR.


Railroad Modifications - Westbank


13/36


Project Site

LA 18 Hwy. 90

Railroad

EXISTING

Huey P. Long Widening ProjectWestbank Railroad Modifications

Existing Site Conditions

To Huey P. Long Bridge

L A 1 8

U S H W Y 9 0


Final Site Conditions

To Huey P. Long Bridge

L A 1 8

U S H W Y 9 0 F u

t u r e R o

a d w a y

Replacement Support





14/36

WestbankSequence of Construction

1. Construct foundations for newcross girders

2. Install falsework to lift existinggirder spans

3. Begin 24 hour rail traffic closure

4. Lift existing girder spans off steeltower

5. Remove upper portion steel tower

6 . Erect cross girders

7. Lower existing girder spans ontonew cross girders

8. Restore rai l t raff ic

9. Remove remaining portion of steeltower

2 4 H O U R R A I L C L O S U R E

START PROJECT

END PROJECT

WESTBANK APPR.

WESTBANK RR MOD

EASTBANK RR MOD

EASTBANK APPR.


Railroad Modifications - Eastbank


Project SiteJefferson Hwy

Clearview Pkwy.

EXISTING

Huey P. Long Widening ProjectEastbank Railroad Modifications

Existing Site Conditions

QWEST Line

V a c a n

t G a s

S t a t i o

n

C l e a r v i e w

P k w y.

J e f f e r s o n

H w y

.

To Hu e y P . Lo ng Br id g e

Power Poles & Power Line

Existing Superstructureand Towers to beReplaced


Final Site Conditions

QWEST Line

V a c a n

t G a s

S t a t i o

n

C l e a r v i e w

P k w y.

J e f f e r s o n

H w y

.

To Hu e y P . Lo n g Br id g e

F u t u r e

R o a d w

a y

F u t u r e

E l e v a t e

d

R o a d w a

y

New Bents



15/36

EastbankSequence of Construction

1. Construct new concrete straddlebents

2. Prepare steel tower and otherfalsework

3. Begin 24 hour rail traffic closure

4. Remove girders under one of thetracks

5. Erect new girders for one track

6. Re-establ ish t rack

7. Restore rai l t raff ic

8. Repeat girder replacement forother track (Steps 3 – 7 above)

9. Remove s teel tower

2 4 H O U R R A I L

C L O S U R E

START PROJECT

END PROJECT

WEST BANK APPR.

WEST BANK RR MOD

EAST BANK RR MOD

EAST BANK APPR.


Approaches & Deck Widening


WEST BANK APPROACH

Start Project Bridge City Ave.Interchange

Conflict w/Existing Rdwy



SimpleThrough

Truss Span EXISTING

PROPOSED WIDENING


EAST BANK APPROACH

End Project

Jefferson HwyInterchange

Conflict w/Existing Rdwy

NOPBRR Spur



16/36


EB APPR.

EB APPR.

Created using Google SketchUp


CAP

TRUMPET

COLUMN

TRUMPET PC

FOUNDATION

W.P.


184 - TOTAL SUBSTRUCTURE UNITS

123 - 4’ X 6’ COLUMN BENTS

4’x 6’8’ x 12’ 6’ x 12’8’ x 14’


Column Type 1: 4’ x 6’





Trumpet for 4’x 6’ columns

4’x 6’

Trumpets for 6’

& 8’ x 12’columns

Trumpet for 8’ x14’ Columns

8’ x 14’

8’ x 12’

6’ x 12’



17/36

TypicalBent

FullHeight

Trumpet

Sub-Trumpet

Size 1

Sub-Trumpet

Size 2

Adj ust Fo oti ng Dept h As Neces sary


WORK PERFORMED IN APPROACH CONTRACT

Main Bridge Deck Widening

East Bank Approach - East Bank Bound

West Bank Approach - West Bank Bound


West Bank Approach

East Bank Bound


WB APPR.Location of West Bank

Steel Girder Spans

East Bank Approach

West Bank Bound


EB APPR.

Location of East BankSteel Girder Spans



18/36


SWITCH TRAFFIC

Project Timeline

• Work Completed – Railroad Modifications – Main Bridge Pier Widening

• Work Under Construction – Main Bridge Truss Widening – West Bank Approach, Main Bridge Deck Widening,

East Bank Approach

Project Schedule

Main Bridge Substructure

Railroad Modifications

SuperstructureFabrication & Erection

Appro aches & Mai n Bridg eRe-d ecking

2012 20132004 2005 2006 2007 2008 2009 2010 2011

Project Status – Completed

Main B ridge Pier Widening• Letting Date:

– December 14, 2005

• Notice To Proceed Date: – April 10, 2006

• Construction Bid: – $ 98,826,907

• Contractor: – Massman Construction Co.

Main Bridge Pier Widening

Pier A Piers I & II Pier III Pier IV

EXISTING

PROPOSED WIDENING



19/36



DistributionBlock




20/36





21/36




New Orleans

G&G Steel



22/36





23/36





24/36


Main Bridge Pier Widening Project Status - Completed

Railroad Modific ations• Letting Date:

– May 10, 2006

• Notice To Proceed Date: – August 28, 2006


• Contractor: – Boh Bros. Construction Co.


Project Site

LA 18 Hwy. 90

Railroad

EXISTING



25/36

Railroad Modifications - Westbank Railroad Modifications - Westbank


New Orleans

G&G Steel




26/36




Project SiteJefferson Hwy

Clearview Pkwy.

EXISTING



27/36

Railroad Modifications - Eastbank Huey P. Long Widening ProjectEastbank Railroad Modifications

Railroad Modifications - Eastbank Railroad Modifications - Eastbank



28/36



Railroad Modifications - Eastbank Project Status – Under Construction

Main Bri dge Truss Widening• Letting Date:

– March 28, 2007

• Notice to Proceed Date: – November 5, 2007• Construction Bid:

– $ 452,605,568

• Contractor: – Massman Construction Co., Traylor Brothers

Inc., and IHI, Inc.


29/36

Main Bridge Truss Widening


SimpleThrough

Truss Span EXISTING

PROPOSED WIDENING

Main Bridge Truss Widening

New Orleans

Industrial SteelConstruction

Gary, IN

Main Bridge Truss WideningTruss Monitoring

STATIC MONITORINGSYSTEM – 433 Members (777

Vibrating Wire StrainGages)

– 5 Piers (10 VibratingWire Tilt Meters)

– WindSpeed/Direction

DYNAMIC (LIVE LOAD)MONITORINGSYSTEM – 31 Members (50

Electrical ResistanceStrain Gages)

Main Bridge Truss WideningWork Platform

Main Bridge Truss WideningWork Platform

Main Bridge Truss WideningFloorbeam Modifications

Template Fit Up Check


30/36


Installation of Wedge Fill


Installation of Wedge Fill

Main Bridge Truss WideningWork on Existing Structure – Bottom Chord

Main Bridge Truss WideningWork on Existing Structure – Top Chord

Main Bridge Truss WideningWidening Truss Bottom Laterals

Main Bridge Truss WideningRemove Existing Sidewalk – Install Temporary Steel Barrier


31/36

Main Bridge Truss WideningMain Bridge Erection - Methods

A = “ Stick Buil d” B = “ Span by Sp an”

A B A B B

Main Bridge Truss WideningMain Bridge Erection






32/36





December 2009


December 2009

Main Bridge Truss WideningContractor’s Erection Scheme – “Span by Span” Erection

• East Anchor Arm• Suspended Span• Through Truss

Span


33/36

Project Status – Under Construction

West B ank Appro ach, Main B ridge DeckWidening, East B ank Approach

• Letting Date: – March 19, 2008

• Notice to Proceed Date: – May 5, 2008


• Contractor: – Kiewit Massman Traylor Constructors

START PROJECT

END PROJECT

WEST BANK APPR.

WEST BANK RR MOD

EAST BANK RR MOD

EAST BANK APPR.




Box Culverts


At Grade Roadways – West Bank


Foundations - Westbank


Foundations - Westbank


34/36


Substructure - Westbank


Substructure -Westbank


Superstructure- Westbank





Approaches & Deck WideningSuperstructure - Westbank


35/36





Created using

Google SketchUp

Substructure – Pier IVA


Substructure – Pier IVA

The Rehabilitation AlternativeHuey P. Long Bridge Case Study


36/36

Q & A1. Priority for the selection of bridges for replacement or rehabilitation with Federal

bridge replacement funds based on three parameters. Name them.

?

2. Of the three parameters above, which is given the highest weight?

?3. What Sufficiency Rating is required for replacement? ?

4. Bridge geometry is a key element of Functional Adequacy and Serviceability.What is the most important f actor within bridge geometry?

?

5. For the case study project, name one key design challenge?

?

6. For the case study project, how was approach bent formwork simplified?

?

bruce peterson handout 6 per page.pdf

Documents