preserving suspension bridge main cablespavementvideo.s3.amazonaws.com/2018nbppc/a1-1 - barry...
TRANSCRIPT
![Page 1: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/1.jpg)
PRESERVING SUSPENSION BRIDGE MAIN CABLES
![Page 2: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/2.jpg)
SUSPENSION BRIDGE CABLE CONSTRUCTION
Aerially Spun (AS) Prefabricated Parallel Wire Strand (PPWS)
Helical Strand (HS)
![Page 3: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/3.jpg)
GLOBAL SUSPENSION BRIDGE INVENTORY
• Twelve (12) countries share over 90% of the inventory
• China surpassed the US in the last two decades
• China and US have the most
• Followed by Japan, Norway & Canada
![Page 4: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/4.jpg)
NORTH AMERICA SUSPENSION BRIDGE INVENTORY
– N.A. has combined total of nearly 30% of the inventory
– Notable US Bridges• Verrazano-Narrows
• Golden Gate
• Mackinac
• George Washington
– Notable Canadian Bridges• Lions Gate
• Angus L. MacDonald
• A. Murray McKay
![Page 5: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/5.jpg)
CONVENTIONAL CABLE PROTECTION
![Page 6: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/6.jpg)
CONVENTIONAL CABLE PROTECTION
![Page 7: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/7.jpg)
Wedged Cable
MAIN CABLE INSPECTIONS
![Page 8: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/8.jpg)
MAIN CABLE INSPECTIONS8
![Page 9: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/9.jpg)
BROKEN WIRES
![Page 10: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/10.jpg)
CALCULATING STRENGTH LOSS10
Stage 1 Stage 2 Stage 3 Stage 4
It is broken and cracked wires that cause strength loss not corrosion.
![Page 11: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/11.jpg)
SAMPLING AND TESTING WIRES
11
![Page 12: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/12.jpg)
NEED TO RE-COMPACT AND RE-WRAP CABLE
12
![Page 13: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/13.jpg)
CABLE WIRE STRENGTH - INCREASE WITH TIME
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1880 1900 1920 1940 1960 1980 2000 2020
Sp
eci
fie
d W
ire
Str
en
gth
(M
Pa
)
Year of Opening
Brooklyn,
Forth Road Bridge,
UK
Verrazano,
USA
George Washington,
USA
Storebaelt East Bridge,Denmark
Humber ,UK
Runyang Yangtze River Bridge,
China
Akashi Kaikyo,Japan
![Page 14: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/14.jpg)
CABLE STRENGTH DETERIORATION
– Water is primary cause for atmospheric corrosion
– Leads to zinc depletion, wire corrosion, and hydrogen embrittlement
– By removing water, one of three components necessary for corrosion & hydrogen embrittlement to occur is eliminated
![Page 15: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/15.jpg)
PAINTING DOESN’T KEEP WATER OUT
Oiling Wrapping
![Page 16: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/16.jpg)
CABLE DEHUMIDIFICATION PRINCIPLES
– Protection of steel through control of RH dates back to research in the early 20th Century
– Discovery of critical RH below which corrosion of steel did not take place (Vernon 1935)
– RH below 60%, substantial reduction in corrosion
– RH below 40%, corrosion practically ceases
![Page 17: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/17.jpg)
APPLICATION OF DEHUMIDIFICATION - BRIDGES
Dehumidification used on bridges
– Steel upper box girder on Humber Bridge, UK and Yeongjong Grand Bridge, Korea
– New & Existing Suspension Bridge Anchorages, Global
New Suspension bridge anchorages• Askoy Bridge (1992)
• Great Belt East Bridge (1998)
• Akashi Kaikyo Bridge(1998)
• Tsing Ma Bridge (1997)
Existing Suspension bridge anchorages• Forth Road Bridge
• Humber Bridge
• Severn Bridge
• Ben Franklin Bridge
• Verrazano-Narrows Bridge
• Anchorage Dehumidification on Humber Bridge dates back to the 1980’s – 35 years ago
• Main Cable Dehumidification on Akashi-Kaikyo Bridge in 1997 – 20 years ago
![Page 18: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/18.jpg)
CABLE DEHUMIDIFICATION SYSTEM
![Page 19: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/19.jpg)
CABLE DEHUMIDIFICATION SYSTEM - LAYOUT19
![Page 20: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/20.jpg)
2016 ICSBOC Page 20
CABLE DEHUMIDIFICATION SYSTEM - WRAPPING
![Page 21: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/21.jpg)
CABLE DEHUMIDIFICATION SYSTEM - SEALING
![Page 22: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/22.jpg)
2016 ICSBOC Page 22
CABLE DEHUMIDIFICATION SYSTEM – INJECTION / EXHAUST
![Page 23: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/23.jpg)
CABLE DEHUMIDIFICATION SYSTEM – INJECTION / EXHAUST
![Page 24: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/24.jpg)
CABLE DEHUMIDIFICATION SYSTEM – PLANT ROOM
![Page 25: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/25.jpg)
CABLE DEHUMIDIFICATION SYSTEM – CONTROLS & MONITORING
![Page 26: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/26.jpg)
MAIN CABLE DEHUMIDIFICATION
– Akashi-Kaikyo Bridge• New Bridge
• Japan, 1997
– Honshu-Shikoku Bridges• Existing Bridges
• Japan, 1997
– Over 25 New & Existing Suspension Bridges Dehumidified
– Nearly 20% Global Inventory
![Page 27: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/27.jpg)
MAIN CABLE DEHUMIDIFICATION - EFFECTIVENESS
Water Removed –UK Bridge (5 Years)
![Page 28: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/28.jpg)
Acoustic Monitoring28
![Page 29: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/29.jpg)
MAIN CABLE DEHUMIDIFICATION - EFFECTIVENESS
Cessation of Wire Breaks
![Page 30: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/30.jpg)
MAIN CABLE DEHUMIDIFICATION
Chesapeake Bay Bridge (Maryland) first full-length main cabledehumidification in North America
![Page 31: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/31.jpg)
MAIN CABLE DEHUMIDIFICATION
From Japan to Europe to North America
19 Years (1997 to 2016)
![Page 32: PRESERVING SUSPENSION BRIDGE MAIN CABLESpavementvideo.s3.amazonaws.com/2018NBPPC/A1-1 - Barry Colford... · –Akashi-Kaikyo Bridge •New Bridge •Japan, 1997 –Honshu-Shikoku](https://reader034.vdocuments.us/reader034/viewer/2022050211/5f5dae045cd70124983aac5e/html5/thumbnails/32.jpg)
CONCLUSIONS
• Conventional means of cable protection not effective
• Water is the main cause of deterioration (corrosion, wire breaks & hydrogen embrittlement)
• Cable Dehumidification demonstrates sustained reduction in RH and wire breaks
• Cable Dehumidification installed on new and existing bridges
• Over 25 bridges dehumidified representing nearly 20% of the global inventory; more in the planning stages
• Slow but now more rapid change in thinking regarding cable protection