Special Considerations for Maintenance of the Sunshine Skyway Bridge

Transcription

1 Florida Department of TRANSPORTATION Special Considerations for Maintenance of the Sunshine Skyway Bridge 2014 NATIONAL BRIDGE PRESERVATION PARTNERSHIP CONFERENCE James J. Jacobsen, P.E. District Structures Maintenance Office Tampa, Florida April 24,

2 Presentation Outline Sunshine Skyway Bridge Overview Proactive Maintenance Program: Skyway Preservation Committee Post Tensioning Protection Improved Inspection and Maintenance Access Bridge Health Monitoring Strategy for a 100-year Bridge Life April 24,

3 Sunshine Skyway Bridge April 24,

4 Sunshine Skyway Bridge Location April 24,

5 Skyway Bridge History In May 1980, a major ship impact caused the south bound main span of the original bridge to collapse. A signature replacement bridge was envisioned. After a 5 year construction period, the bridge was opened to traffic in April The bridge was re-dedicated in 2005 as the Bob Graham Sunshine Skyway Bridge as the former Florida Governor had the vision to build this signature bridge. Owned and Maintained by the Florida Department of Transportation Asset Maintenance Contracted since 2004 April 24,

6 Looking south April 24,

7 Looking North April 24,

8 MAIN SPAN UNIT Post-Tensioned Precast Segmental Box 42 Continuous Stay Cables, 21 per Pylon Total Length: 4,000 ft April 24,

9 HIGH LEVEL APPROACH HIGH LEVEL APPROACH Post-Tensioned Precast Segmental Boxes Post-Tensioned Precast Segmental Columns Length: 2,430 ft each April 24,

10 LOW LEVEL TRESTLE SPANS LOW LEVEL TRESTLE SPANS Shldr. Lane Lane Shldr. Shldr. Lane Lane Shldr. Cast In Place Deck on Prestressed Concrete Beams Total Length: 13,000 ft April 24,

11 High level approach April 24,

12 High Level Approach Column and Dolphin April 24,

13 Proactive Maintenance Program Major Challenge: Preserve the Investment Response: Skyway Preservation Committee April 24,

14 Total Cost Per Year to Maintain April 24,

15 Major Maintenance Challenges Corrosive Environment Three types of bridges in one Access for Maintenance April 24,

16 Skyway Preservation Committee The Preservation Committee exists to provide a forum whereby a select group of specialists come together twice per year to discuss a wide variety of issues that affect the current and long term health of the Skyway Bridge. April 24,

17 Sample Skyway Preservation Committee Meeting Agenda Items Recently completed repair contracts Accelerometers on Stay Cables Remove Anchorage Covers Stay Cable Tension Testing Median Interior Maintenance Corrosion Prevention (water line and foundation) April 24,

18 Post Tensioning Protection Five Strategies: New Direction for Florida: PT Bridges (2002) 1. Enhanced PT system 2. Multiple tendon Paths 3. Fully grouted tendons 4. Water tight bridge 5. Multiple layer anchor protection April 24,

19 Where could water enter? Closure pour cracking PT anchor pour-backs Raised median Segment joints (dry and epoxy coated) Cracked Polyethylene Ducts April 24,

20 Where could water enter? April 24,

21 Sealing the Raised Median Barrier with Polyurea April 24,

22 Cable Stay / Median Barrier April 24,

23 Segmental Bridge Deck April 24,

24 2013 Deck Sealing Test Area Methyl Methacrylate April 24,

25 2013 Deck Sealing Test Area Methyl Methacrylate April 24,

26 Polyethylene Ducts All External PT ducts had been wrapped with heat shrink sleeves by Ongoing maintenance includes localized repairs by asset maintenance forces. April 24,

27 Localized Heat Shrink Duct Wrap Repair April 24,

28 Special Inspection of Post Tension Systems The Post Tension System is a critical item to inspect and ensure proper performance Voids and segregated grout must be detected and corrected to ensure maximum life of post tensioning system Special inspection methods are needed beyond the routine visual inspection April 24,

29 Typical External Tendon Cross Section High Density Polyethylene Duct Strand Cement grout April 24,

30 Post Tensioned Tendon Inspection State of the Art No single test method is able to effectively inspect and detect tendon voids and corrosion Current methods can be expensive and time consuming: Main Magnetic Flux Several methods may need to be combined to get better results The FDOT is supporting new development in non destructive testing April 24,

31 Cable Stay Repainting April 24,

32 Cable Stay Repainting April 24,

33 High Level Approach Bearing Inspection April 24,

34 High Level Approach Maintenance Typical High Level Approach Transition Pier from Single to Dual Box Sections April 24,

35 Sealing Column Caps April 24,

36 Pier Cap Sealing Complete April 24,

37 Wind Driven Rain Under Segments April 24,

38 Improved Inspection and Maintenance Access April 24,

39 Rappelling Tower April 24,

40 Bore scope Inspection of Stay Saddles Check for corrosion and coating condition April 24,

41 Suspended Scaffolding April 24,

42 Inspection of Stay Cables using High Lift April 24,

43 Inspection of Stay Cables using High Lift April 24,

44 Inspection of Stay Cables Using High Lift April 24,

45 New Access Hatches in Median April 24,

46 Inspection Inside Median Barrier April 24,

47 Sunshine Skyway Health Monitoring Integrated methods of monitoring bridge condition properties April 24,

48 Outline Need for Monitoring Existing Monitoring System Structural Health Monitoring Goals April 24,

49 Structural Health Monitoring (SHM) Why Monitor the Skyway? Vital to regional and multimodal transportation Help ensure 100 year design life is met Detect problems between visual inspections Post hurricane or impact evaluation Provide live weather conditions for Traffic Management April 24,

50 Current Monitoring System Global Positioning System (GPS) Receivers Automatic Total Stations Weather Stations Analytical Model April 24,

51 GPS System GPS Sensors: Leica GPRX 1200+RS500 Receivers Post-processed accuracy of 1 centimeter in x and y planes April 24,

52 GPS Receiver Locations April 24,

53 Automatic Total Stations Leica TCA2003 ATS on Dolphin 101 Leica TM30 on Dolphin 104 Accuracy to 1 millimeter Redundancy for GPS April 24,

54 ATS Prism on Tower April 24,

55 ATS Lines of Sight April 24,

56 Weather Station Weather Sensors Wind Speed/Direction Temperature/Humidity Barometric Pressure Internet-connected with live web-cams Rain Gauge April 24,

57 Weather Station Website Tabular and graphical data available Website updated every 15 minutes April 24,

58 Structural Health Monitoring (SHM) Goals: Design verification (with analytical model) Establish normal movement Extreme event monitoring Deterioration/settlement detection April 24,

59 Design Verification Theoretical estimation of time-dependent stay forces to compare with empirical test results Calibration/verification of GPS/ATS readings April 24,

60 Analytical Model Time-dependent frame analysis model MIDAS Civil software used Main model P6S (106) to P6N (117) April 24,

61 Wind Analysis Graphical Results 1.37 ft 1.01 ft April 24,

62 Normal Operating Parameters April 24,

63 Extreme Event Monitoring Hurricane effects Ship Impact Wind/rain cable vibration April 24,

64 Future Goals Fully calibrated analytical model Establish thresholds of movement Additional permanent sensors Strain measurements Stay vibration measurements Thermal measurements Automated alerts April 24,

65 Strategy for a 100 year Bridge Life: Continue a Preventive focused inspection and maintenance program Continue the "Skyway Preservation Committee to sustain the vision for a 100 year life for the bridge Give special attention to long term Corrosion Prevention April 24,

66 Questions? April 24,

67 NATIONAL BRIDGE PRESERVATION PARTNERSHIP CONFERENCE Special Considerations for Maintenance of the Sunshine Skyway Bridge Thank you for participating Florida Department of Transportation District Structures Maintenance Office Tampa, Florida April 24,