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Review of Maintenance Prioritization Schemes from Three Transportation Authorities. Christopher L. Farschon, P.E., PCS Greenman – Pedersen, Inc. Coatings Group October 7, 2009 NACE Eastern Area Conference. Why Prioritize Bridge Painting?. Why Prioritize? PLANNING. Money Money Money
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Review of Maintenance Prioritization Schemes from Three Transportation Authorities Christopher L. Farschon, P.E., PCS Greenman – Pedersen, Inc. Coatings Group October 7, 2009 NACE Eastern Area Conference
Why Prioritize? PLANNING • Money • Money • Money • Define an acceptable state of existence • How coating conditions affect a bridge throughout its lifetime • Identify what funding is needed to meet that need • Justify painting budgets
Where to Start Planning? • Bridge type • Size • Proximity • Location • Traffic Conditions • Deck • Substructure • Future Rehabilitation • Coating and Corrosion Condition
Design Monitor Learn Goals of a Prioritization Program • Vary by Agency • Lowest overall cost (today, life cycle, year 20?) • Define needed funding • Meet constraints • Integrate with other work • Improvements • Traffic • Aesthetics • Be adaptable
Three Authorities • A - Toll Authority 1 • Major structures only (9 facilities – 26M square feet) • Metropolitan area • 100% self funded • B - Toll Authority 2 • Major highway (hundreds of bridges – focus on 16) • Urban / Metropolitan / Rural • Combination funding • C - State DOT District • Over 1,000 bridges (focus on overpasses) • Metropolitan and Suburban area • Federal / state funding
Historical - Toll Authority A • Years of “as-required” maintenance painting • Increasing environmental concerns • Increasing steel repair frequency • Painting Program was planned around 1990, implemented 1993-1995 • Unofficial Program Goals • Reduce lead paint liabilities • Reduce as-needed steel repairs • Improve bridge appearance • Define needed funding
Program Description – Toll Authority A • Based on a facility wide survey conducted in 1993 • Categorizes bridge areas based on paint conditions and “local” environments • Appropriate painting is performed in each area to minimize costs • Access costs very high = minimal contracts • One contract – multiple Items – multiple methods
Program Goals – Toll Authority A • Maintain an acceptable paint condition while maintaining budget goals • Coordinate with Capital improvement projects and biennial inspections • Address highest priorities within 12 years
Yearly Costs – Toll Authority A Average = $21.4M per Year Average = $14.9M per Year
Unit Cost Trends – Toll Authority A • Low early – High middle – Lower recently • Worst corrosion addressed first • Large projects (economies of scale were good) • Concurrent with some maintenance • Aesthetic areas • Hold until re-paint • Combination / Rehabilitation Projects • Difficult projects? • Some shared costs • Some additional costs • Maximize shop painting
Cost/Specification Factors- Authority A • Size of the project • Mobilization and staging areas • Access to work- placement of equipment • Lane closures, water - barge etc. • Environmental controls • Inspection requirements - warranty • Configuration or type of structure • Labor, equipment, and material costs • Bidding climate (other work, available bidders)
Program Summary – Toll Authority A • Budgets were justified • Funding allocated • Projects designed • Conditions were monitored with database population • Influenced priorities on a biennial basis • Program is in place that relates painting needs to available time to needed funding • Needs not always driven by conditions
Toll Authority - B • Program recently enacted to prioritize painting of major structures • Not an authority-wide plan (16 of several hundred structures, but the most significant 16) • Works around/with major capital programs • Coordination with other maintenance work • Constructability a key factor
Project Background – Toll Authority B • Program has 2 objectives: • Part 1 - The investigation and assessment of the existing coating system on 16 major bridges, development of a prioritized list of bridges requiring repainting, and recommendations related to bridge painting as part of a Ten Year Capital Program • Part 2 - The design and development of documents for two (2) Major Bridge Repainting contracts
Budget / Financial – Toll Authority B • Predetermined budget and timeframe • anticipated value of $250M • 10 year effort • Prioritize the needs based on constraints, coordination, conditions • Generate project specific engineer’s estimates for near-term painting costs
Bridge Surveys – Toll Authority B • Technical Paint Condition Data – Adhesion, thickness, lab tests, visual survey data for paint (peeling and corrosion) • Development of square footage quantities • Other considerations - Deck and Joint condition, planned rehabilitations and prior painting work
Painting Options – Toll Authority B • Total Coating Removal and Replacement • Zone Coating Repair (Beam Ends, Bearings, Weathering Steel) • Maintenance Spot Painting and Full Overcoating
Prioritization – Toll Authority B • Rough Budget Estimates – Key to project designs and evening out the workload across the program duration • Coordination with other work – Use of the deck condition study data, coordination with completed deck/rehabilitation projects and the capital improvement projects • Prioritization factors • Condition of the existing coatings and extent of corrosion • Condition of the existing deck • Availability of construction staging areas • Complexity of maintenance and protection of traffic • Complexity of containment • Environmental impacts • Outside agency coordination
Project Sequencing – Toll Authority B • Projects of constructible size and duration were appropriately prioritized / sequenced • Highest 2 priorities under design /construction • Update survey needed • Project was a snapshot of conditions combined with other available data to make the most appropriate prioritization today • Future survey will justify extending durations before painting or accelerating certain projects
Program Summary – Toll Authority B • Select group of bridges • Projects designed and estimated to fit available budget • Technical data / conditions were not always the priority driver • Program is based on a snapshot survey of facilities • Follow-up survey will be needed
Authority C • State Department of Transportation District • 1998 project • Over 1,000 bridges • Majority are highway overpasses and smaller structures • Semi “Automated” database system • Used condition data, constraints, project-specific factors • Prioritization was based on Return on Investment
Technical Basis – Authority C • Historical data for coatings in appropriate environments defines degradation rates • Survey characterizes exposure conditions and technical paint data • Lowest cost painting option is selected using an ROI calculation • Current coatings and corrosion condition ratings • Exposure environment ratings • Predicted life to next painting event
Program Summary – Authority C • Database program generates a list of structures sorted by ROI • DOT organizes projects to address priorities (human factor is required) • Condition data easily attained • Degradation models and cost factors were fixed • Constraints were variable • Does not estimate budgets
Common Threads • All prioritization programs were custom • Authority constraints were custom • All used existing data sources with enhancements • All need maintenance to remain accurate • All provide a starting point for defendable analysis
Feedback is Needed • Programs are tools – use for designated purpose and within limitations Design Monitor Learn
Conclusions • Maintenance painting is needed • All painting can be scheduled with the most benefit (least cost) by evaluating structures and implementing a maintenance painting program • Numerous “constraints” affect a program • Other work • Cost trends • Priorities / Goals • Program must be adaptable • Use existing data or existing inspection activities