VDOT s Strategic Approach to Bridge Management and Maintenance

Transcription

1 ASCE Richmond Branch VDOT s Strategic Approach to Bridge Management and Maintenance Adam Matteo Assistant State Structure and Bridge Engineer Structure and Bridge Division October 13, 2015

2 Long Term Challenge - Bridge Maintenance and Management 35 Year Outlook Replace bridges only when Necessary Focus on Timely, Targeted Repair and System Preservation Tools For Making the best Business Decisions 2

3 Over 13,000 Structures 4,500 4,252 4,000 3,842 3,500 3,458 3,000 No. of Structures 2,500 2,000 1,500 1,562 2,332 2,115 1,715 1, 's 2000's 1990's 1980's 1970's 1960's 1950's 1940's 1930's 1920's 1910's 1900's Decade Virginia Structures Built by Decade 3 * County Bridges added to the VDOT Inventory during this period with unknown construction dates (Assumed year built equaled year added to system)

4 Traditional Philosophy Emphasis on New Structures - Natural Bias Condition-Based Replacement when Deterioration Becomes Too Extensive 4

5 FY13 Distribution of Bridge Spending Millions Restorative $31 (11%) $9 (3%) Major Rehab $52 (19%) Reconstruction (Maintenance Funds) $138 (50%) Total FY13 = $284M = $190 Maintenance + $94 Construction 2/3 of Expenditures on Replacement $44 (16%) Reconstruction (Construction Funds)

6 Replacement costs in Millions $1,800 $1,600 $1,400 $1,200 $1,000 $800 $600 $400 $200 Total Replacement Costs 35 Year Outlook to Replace Bridges at Age 70 Costs for Bridges Currently Structurally Deficient or Currently Over 70 are Spread over the Next 25 Years $180M Peak Annual Bridge Construction Funding 6 $ Year 2050

7 50 35 Year Funding Outlook to Replace Bridges at Age 70 Total Replacement Cost - $Billions $6 Available $44 Needed

8 8 Prieto Slide

9 Alternate Strategy Timely, Pro-Active Preservation Interventions Targeted Repairs Condition-Based Replacements Only When Absolutely Necessary 9

10 The Causes Bridge Deterioration The Majority of Bridge Deterioration is Attributable to Corrosion: Leaking Joints Leading to Beam End and Substructure Deterioration Porous Concrete Leading to Corrosion of Reinforcement Salt Water Other Problems: Fatigue Impact Geotechnical issues Scour 10

11 Proven Solutions are Available Preservation Techniques Epoxy Overlays Rigid Overlays Joint Elimination Joint Improvement Painting Beam End Coating Targeted Repairs Rigid Overlays Beam End Repair Substructure Surface Repair 11

12 The Importance Of Timeliness Damage Initiation Phase Damage Propagation Phase Replace/ Failure Cost of Maintenance First Visible Damage Able to Identify Causes of Deterioration Able to Predict Time to Deterioration Worst First Repairs Proactive Maintenance Good Condition: Preserve Fair Condition: Extend life Condition of Structure Poor Condition: Replace

13 Replacement is Sometimes the Most Appropriate Solution Highly Deteriorated Culvert

14 Replacement is Sometimes the Most Appropriate Solution Highly Deteriorated Timber Deck Bridge

15 Working Toward Indefinite Life Condition of Structure Repair and Preservation Initial Condition Timely Action Deterioration without Preservation Slowed Deterioration Second Intervention Age - Years

16 Investing in the Future Fix the Damage and Keep the Roof Sealed 16

17 Backwall Deterioration Deterioration at Edge of Joint 17

18 Typical & Regular Joint Failure Leads to Deterioration Deterioration of Concrete Supports Corrosion of Steel Beams /Girders 18

19 The Importance of Preventive Maintenance - Decks 19

20 Investing in the Future Targeted Repairs 20

21 Steel Beam End Repair - Before

22 Steel Beam End Repair During Construction

23 Steel Beam End Repair - Final

24 Superstructure and Substructure Surface Repair

25 Superstructure and Substructure Surface Repair

26 Superstructure and Substructure Surface Repair

27 Superstructure and Substructure Surface Repair

28 Investment Strategies Preservation Strategies 28

29 Fast Track Hydrodemolition 29

30 Fast Track Hydrodemolition

31 Deep Hydro Structural Overlay 31

32 Deep Hydrodemolition

33 Deep Hydrodemolition 33

34 Deep Hydrodemolition Concrete Overlays 34

35 Eliminating joints by constructing joint closures at piers 35

36 Eliminating joints by constructing joint closures at piers 36

37 Project Examples 37

38 38

39 Fast Track Hydrodemolition 39

40 I-64 over Shockoe Valley After Overlay 40

41 I-64 Over Shockoe Valley Project Summary Repair and Preservation Overlay $6M Beam Repairs $2M Painting $11M Substructure Surface Repair $2M Joint Elimination $1M (at a later date) Total $22M Replacement $125M 41

42 I-64 over Dunlap Creek Overlay and Joint Elimination 42

43 I-64 over Dunlap Creek Eliminated Joint 43

44 I-64 over Dunlap Creek Hydromilled Surface 44

45 I-64 over Dunlap Creek Placement of Overlay 45

46 Business Principals Tools for Good Decision-Making 46

47 Bridge Durability New Construction Emphasis on Value of Investment Small Cost Increases Substantially Improving Durability Better Culvert Materials Durability Of VDOT S Structure Inventory 3 Coat Zinc Coatings High Performance Concrete Corrosion Resistant Reinforcement Jointless Bridges Low Paste Deck Concrete Year Implemented

48 Using Valuation as the Basis for Engineering Decisions $1,200,000 Structure Depreciation $1,000,000 Current Value of Asset (Equity) $800,000 $600,000 $400,000 $200,000 $- Initial Value ($1M) Decision Residual (Salvage) Value Option 1 Replace with Steel Culvert $1M $(200,000) Age - Years

49 The Benefits of Using Equity as the Basis for Engineering Decisions $1,200,000 $1,000,000 Current Value of Asset (Equity) $800,000 $600,000 $400,000 $200,000 $- Decision Option 2 New Concrete Culvert $1.15M $(200,000) Age - Years

50 The Benefits of Using Equity as the Basis for Engineering Decisions $1,200,000 $1,000,000 Option 3 Line Culvert $250k Current Value of Asset (Equity) $800,000 $600,000 $400,000 $200,000 $- Decision $(200,000) Age - Years

51 With Equity Curves Simple Life Cycle Analysis is Practical Name Initial Construction Traffic Control Initial Costs Engineering, Inspection, R/W Total Initial Cost Estimated Maintenance Costs Per 10 Year Interval Replace ment Year Present Value (calculated) Option 1 Coated Steel $748,400 $64,500 $187,100 $1,000,000 $4, $1,131,192 Precast Option 2 Concrete $850,240 $87,200 $212,560 $1,150,000 $6, $893,554 Option 3 Steel Liner $190,000 $12,500 $47,500 $250,000 $4, $1,380,666 Discount Rate 1.50% Suggested PE, CEI, R/W Factor 0.25 Steel Liner Option Assumes New Steel Culvert Required in 25 Years 51

52 Conclusions Think of each project in the context of the larger picture Use timely preservation strategies Make the best life-cycle investments 52