bridge maintenance strategies -...

Bridge Maintenance Strategies Peter Weykamp, P.E.

Bridge Maintenance Program EngineerNew York State Department of Transportation

•Definitions•Conditions•Needs•Support•Bridge Elements

BACKGROUND

DEFINITIONS• Maintenance: a network

level, long-term strategy that enhances bridge performance by using an integrated, cost-effective set of practices that extend bridge service life, improve safety, and meet motorist expectations.

– Or anything done to a bridge short of a deck replacement.

PREVENTIVEPREVENTIVEMAINTENANCEMAINTENANCE

CORRECTIVE CORRECTIVE REPAIRSREPAIRS

CYCLICAL CYCLICAL MAINTENANCEMAINTENANCE

DEFICIENTFHWA - A bridge is “structurally deficient”if either the superstructure, substructure, or deck is rated less than 5 on a 9 point scale.

NYSDOT CONDITION RATING

• “Deficient”– Weighed average

condition < 5.0

• Rating Scale– 1 – Failed condition– 3 – Serious deterioration– 5 – Functioning as

designed– 7 – New condition

• Weights– Primary member 10– Abutments 8– Piers 8– Structural Deck 8– Bridge Seats 6– Bearings 6– Wing & Backwalls 5 – Secondary member 5– Joints 4– Wearing surface 4– Sidewalks 2– Curbs 1

Number and Status of Bridges in the US(12% SD, 13% FO)

0

20,000

40,000

60,000

80,000

100,000

120,000

Pre1910

1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s

Decade Built

Num

ber o

f Brid

ges

0%

10%

20%

30%

40%

50%

60%

70%

80%

% o

f Def

icie

nt B

ridge

s

Number of Bridges % of Deficient Bridges

Source: 2007 NBI

State and Local Highway Bridge Condition Trends

40

45

50

55

60

65

70

75

80

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

% Goo

d an

d Excellent by N

umbe

r

Year

Local Bridges State Bridges

Deficient Bridge Wave

0

100

200

300

400

500

600

700

800

900

<3 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5 5.7 5.9 6.1 6.3 6.5 6.7 6.9

New York State Rating

Num

ber o

f Brid

ges

Local Bridges State Bridges

1450 bridges become deficient in next 5 years

1500 additional bridges become deficient in next 6-10 years

ASSESSING NEEDS• Inspection data

– Focus on safety

• Models focus on rehab/replace

• Maintenance candidates – Real vs. ideal needs

• Decision support systems– Domestic scan of lead States

MAINTENANCE NEEDS

0%

100%

Time

BR

IDG

E C

ON

DIT

ION

• Bad– Rehab/Replace

• Good– Preventive/Cyclical

• Fair– What has to get done?– What are the

consequences of deferred action?

FAIRFAIR

BAD

GOOD

FUNDING• Federal formula

– Based on deficiency – Rewards poor stewardship– Some flexibility

• Organized to build the interstate system• Few advocates for bridge maintenance • “Follow the Money”

BRIDGE PARTS

CEU QUESTIONS

Current Practices in Bridge Maintenance

PART 1 

EXPANSION JOINTS• All Joints Leak• Armored Joints

– Constructability– Repair-ability– Safety hazard– Deterioration

ARMOR-LESS JOINTS• Elastomeric Concrete

– Polymer based– “Maintenance friendly”– Rapid setting– EXPENSIVE

• Seals– Repairable

• Liquid

• Pre-formed

INTEGRAL ABUTMENTS

INTEGRAL ABUTMENTS• Simple joint• Minimal substructure• Low Maintenance• Design Hierarchy

– Integral– Joint-less– Joint expansion end– Joints on both ends

• Large skews• Unbalanced spans, etc

PROTECTIVE COATINGS

• Lead-Based Primers– Safety concerns

• Moisture-cured Urethane– Over-coating– Total Removal– Moisture tolerant

CONCERNS

• Surface Preparation • Health & Safety

– Containment• Cost

– Service Life– Performance

• New Primer– Zinc

ALTERNATIVES• Weathering Steel• Concrete• Timber• New Coating Systems

WEATHERING STEEL

• Self-protecting– Patina

• Aesthetics• Environment

– Health & Safety• Needs Wet/Dry

Cycles

P/S ADJACENT BOX BEAMS

• Plant Q/C• No Painting• Rapid Construction• Low Initial Cost• Freeboard

– Pressure flow• Debris

CONCERNS• Longitudinal

Cracking of Decks– Working Cracks

• Limited treatments

• Deck Deteriorates• Unknown Beam

Condition

OPEN GRATED BRIDGE DECKS

• Super and substructure deterioration

• Eliminated

REINFORCING STEEL

• Bare Bars – Premature full-depth

cracking

– SIP forms• Corrosion evident

• Epoxy Bars– Proven success– Min. increase in $

• Stainless– Justifiable

UNCOATED REBAR

HP CONCRETE

• Pozzolans – Fly Ash & Silica Fume

• High Strengths• Low Permeability• Shrinkage Cracking

– Increased permeability

BRIDGE BEARINGS• Steel Bearings

– Lubrication Required– Can’t meet 4 year cycle

• Jack & Clean• Often “Freeze”

– Thermal Stresses• Replacement Program

– Elastomeric Bearings– “Maintenance Friendly”

CONTEXT SENSITIVE DESIGN

PREVENTIVE MAINTENANCE

TASK CODE DESCRIPTION CYCLEH11 Clean Substructure 2 yrs H13 Seal Substructure 6 yrs

H29 Lubricate Bearings 4 yrs

H38 Clean Superstructure & Deck 2 yrs

H58 Remove Wearing Surface 12 yrs H59 Place Wearing Surface 12 yrs H60 Place Waterproof Membrane 12 yrs H69 Seal Deck 4 yrs H73 Fill Cracks & Joints 4 yrs

H75 Clean Drainage Systems 2 yrs

H89 Bridge Painting 12 yrs

SPOT PAINTING

• Resume Program• Materials

– Calcium Sulfonate

• Needle Scalers• Vacuum Tools • Minimal

Containment Necessary

DECK TREATMENTS

• All Concrete Cracks– Transverse– Longitudinal– Map

• New & Old Concrete• Treatments

– Fill cracks or– Bridge cracks

RADAR Statistical Analysis• Inspector rating supported• GPR sees things the

inspector doesn’t• Rating alone cannot be

used for selecting deck treatment

• Deterioration is age related• Age and % delamination

are not correlated

FILLING CRACKS

BRIDGING CRACKS

PM & MINOR REPAIRS

4.4

5.8

$250K

$5K

2370 Good Bridges

4740 Fair Bridges

790 Poor

$3.7M

Treatment Costs / Bridge

Maintenance Candidates

Major Rehab or Replacement Candidates

MAINTENANCE DESIGN• Weathering Steel• Composite Design• Simple Span

– No pier in water• Integral Abutment

– No joints– No bearings

• Epoxy Bars • Bridge Railing

– No sidewalk

Best Practices in Bridge Management Decision Making

PART 2 

Bridge Management Decision MakingDomestic Scan Tour

Discover and collect information on how DOTs manage maintenance of highway bridges and how maintenance impacts the overall bridge program

Focus on decision processes for maintenance programs;How Do Decisions Rely On:

• Bridge Conditions• Maintenance Needs• Effectiveness of Maintenance• Funding Availability

AASHTO

FHWA Consultant

Academia

Bruce JohnsonOregon DOT

Scot BeckerWisconsin DOT

Tod KimballFHWA Vermont

Narendra KhambhatiArora and Assoc., NJArt D’Andrea

Louisiana DOTKeith RamseyTexas DOT

George HearnUniv. of Colorado

Pete WeykampNew York DOT

WA

CA

MI

OH

FL

DE

VA

Washington DOT

California DOT &  El Dorado/Placer County DOTs

Michigan DOT

Ohio DOT

Florida DOT & Turnpike

Delaware DOT

Virginia  DOT

Inputs

.

Site Visit

Scan Team

Document Review

Bridge Management Process

Preventive Maintenance

Agency Support

KEY FINDINGS

•Maintenance Needs•Prioritization•Performance                                                Measures•Verification

Bridge Management

Statewide -- State Owned

0

5000000

10000000

15000000

20000000

25000000

30000000

35000000

40000000

45000000

50000000

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Calendar Year Data

Squa

re A

rea

of B

ridge

s

Non Deficient Total deficient

New York

0

200

400

600

800

1000

1200

1400

Num

ber o

f Brid

ges

1 2 3 4 5 6 7 8 9

NBI Rating55

GoodFairPoorSerious or Critical

Michigan

Identified at the element level  Uniform, specific, and repeatable  Stated as standard work actionsAccessible throughout the agency

Maintenance Needs

NBI CONDITION ASSESSMENT Ohio

TYPESModified NBI Commonly Recognized (CoRe) Bridge ElementsOwn system

SUPPORTSDetailed reportsMaintenance decisionsTreatment options Early interventionMinimize repair costs

Element Level Inspection

INSPECTION FORM                    OHIO

Uniform, Specific, & Repeatable

METHODSInspectors recommend actionDrop-down menuActions prioritizedCosts per actionStored in database Draft work order

Needs Database New York

Needs Database        Oregon

Inspector Recommendations  Washington

Integrate objectives for deficiencies, preventive maintenance, network performance, and risk.

Engage both central and regional DOT.

Advance from network‐level rankings to selection of specific projects.

Prioritization

Prioritization Formulas• Sufficiency Rating (NBI) Structural Adequacy and Safety (55% maximum);

Serviceability and Functional Obsolescence (30% maximum);

Essentiality for Public Use (15% maximum); Special Reductions 

• Health Index (Pontis)Health Index (HI) = (∑ CEV ÷ ∑ TEV) × 100

TEV = Total element quantity × Failure cost of element (FC)

CEV = (∑ [Quantity in condition state i × WF(i)]) × FC

Health 80-89 Health 70-79 Health below 70

Deficiency Form

ula

Del

awar

e

Maintenance Accountability Program  Washington

Match objectives in bridge maintenance

Identify work to advance maintenance objectives 

Provide simple indications of status of bridge networks

Virginia

Performance Measures

4A2 Structural Bridge Repair             

2007-09 M Program Budget: $9.2 million

Bridge inspections result in the “to‐do list” of smaller‐scale structural repairs for the Maintenance Program to complete.  Examples of these repairs include: Bridge Cap Repair

Bridge Column RepairDebris RemovalScour RepairExpansion Joint Repair

Washington

4A2 Performance Measurement

A: 90 -100% completedB: 80 - 89% completedC: 65 - 79% completedD: 50 – 64% completedF: Less than 50% completed

The performance measurement for this activity focuses on Priority 1 repairs. The of repairs for is compiled annually.

The Level of Service is based on the percentage of Priority 1 repairs completed.

Level of Service target is a C

2008 Level of Service delivered is a D

The 2009-11 proposed budget includes an additional $1.5 million to catch up with this maintenance backlog and achieve the target.

Washington

Bridge Maintenance Contract Funding and Backlog

$94

$63

$63

$94

$94

$94

$13

$9$6$6$6

$94

$94

1645

2883

2922

2961

3000

3039

3078

3117

2844

1870 20

95 2320 25

44

$-

$20

$40

$60

$80

$100

$120

$140

$160

$180

$200

01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11 11/12 12/13 13/14Fiscal Year

Fun

ding

Lev

el (M

illio

n $)

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

# of

Bri

dges

Funding $ Backlog Bridges

Actual Projected

71

Bridge Maintenance Program 2001 - 2005

CalTrans

Bridge Maintenance Contract Funding and Backlog

$94

$63

$63

$94

$94

$94

$13

$9$6$6$6

$94

$94

1645

2647 28

35

2874

2913

2952

2991

3030

2507

1870 20

95 2320 25

44

$-

$20

$40

$60

$80

$100

$120

$140

$160

$180

$200

01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11 11/12 12/13 13/14Fiscal Year

Fun

ding

Lev

el (M

illio

n $)

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

# of

Brid

ges

Funding $ Backlog Bridges Reduce Backlog

2007 & 2009 Five Year Plan

Actual

72

CalTrans

Strategy is effectiveInvestment pays off   

Needs are metLevel of Service indicatorsNeeds – Accomplishment = Gap

Work completed  Report into BMS, MMS, Capital Program, …

Verification

74

1,333 BridgesCurrent - 11%

Goal – 5%

8,623 BridgesCurrent - 69%

Goal – 85%

2,544 BridgesCurrent - 20%

Goal 10%300 Bridges/Yr

Rehab. Program (SHOPP)

Maintenance Program Preservation Program(Major Maintenance)

40 Bridges/Yr

870 BridgesCurrent - 7%

Goal – 5%

9,122 BridgesCurrent - 71%

Goal – 85%

2,835 BridgesCurrent - 22%

Goal 10%560 Bridges/Yr

Rehab. Program (SHOPP)

Maintenance Program Preservation Program(Major Maintenance)

20 Bridges/Yr

CALTRANS

Preventive Maintenance

Significant part of programApplied before bridges become deficientImplements clear plans of actionFlexible allocation of resources

Washington

Tracking Trends    Michigan

Deterioration RateStatewide Trunkline Bridges

0

50

100

150

200

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Year

Num

ber B

ridge

s G

oing

fro

m G

ood/

Fair

to P

oor Linear Fit

76

Bridge Deck Preservation Matrix     Michigan

77

Cyclical Maintenance Virginia

78

Bridge Deck Washing (Concrete) – 1 YearBridge Deck Sweeping – 1 YearSeats & Beam Ends Washing – 2 YearsCutting & Removing Vegetation - 2 YearsRoutine Maintenance of Timber Structures - 2 YearsReplacement of Compression Seal Joints – 10 yearsScheduled Replacement of Pourable Joints – 6 yearsCleaning and Lubricating Bearing Devices – 4 yearsScheduled Beam Ends Painting – 10 YearsInstallation of Thin Epoxy Concrete Overlay – 15 YearsRemoving Debris from Culverts – 5 Years

Bearing Replacement Program     New York

79

LEGISLATURE: gas tax, dedicated fund, MPOpercentage

DOT Executives: Maintenance is not a episodic.ODOT – “Fix it First”

DOT Central: Use quantitative performance measures, Recognize districts’ first‐hand knowledge 

District Engineers: Evaluate needs and trends funds and projects

Inspectors: Identify needs, recommend actions 

Crews: Execute work, take initiative

Agency Support

Funding Levels

Michigan– Fixed: 22% PM, 30% Rehab, 48% Replace

Ohio, Washington– 15% to MPOs (Fed. legislation @ 15% min.)

Virginia– Majority of $ maintenance - legislated

California– PM from $6M to $94M

State Gas Tax– NY 42.5; Ca 39.9; Wa 37.5; Fl 34.5; Mi 30.9

DIRECTION“Service-life Extension”

MobilityAdvances in Materials

Concrete repairs, CoatingsInnovative Designs for In-

service BridgesDeck replacement optionsRapid replacement

Culverts

Comparative MeasuresPartnerships

Industry, ConsultantsRegional GroupsCommunicationOwners, LegislaturesTriagePosted & Closed AssessmentTreatmentsHolistic

Management

CEU QUESTIONS

We, the bridge maintenance engineers of New York, hold these truths to be

self-evident: all joints leak, all concrete cracks, and rust never sleeps. We will

strive to capitalize our way out of maintenance and maintain our way out of capital. It is our endeavor to educate others that a bridge is as important to a

highway as a diamond is to a ring.