Bridge Deck Life Study

1
Bridge Deck Life Study

• Progress Report Sept. 13, 2001

Dan Fisher, Assistant Professor Oklahoma State
University
2
Objectives

• Correlate bridge deck life with salt use
• Estimate maintenance costs associated with salting

3
Study Parameters

• Interstate highway system bridges
• Constructed in early 60s
• Relatively uniform standards and methods from
  state to state
• Bridges in large metro areas
• High traffic
• Critical arteries

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Overall Approach
no exit from the loop!
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State DOT Data

• Inspection reports
• Universally available
• Bridge-by-bridge data
• Contain no maintenance or repair info.
• Contract reports
• Major repair and replacements only
• part of the story
• Usually provides bridge-by-bridge data

6
State DOT Data

• Maintenance reports
• not bridge-by-bridge data
• Not well organized
• Salt use reports
• Almost non-existent
• Purchase orders or invoices

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Sources of Existing Data

• TRIS database (Transportation Research
  Information Service)
• Local studies contacts
• Starting point for additional data collection
• ITDB database (Intermodal Transportation
  Database)
• To be explored

8
Current Target States

• No Salt State California
• LA freeways valley side
• Good contacts, good data
• High Salt State Illinois
• Chicago freeways
• Good contacts, excellent data
• Moderate Salt State Oklahoma
• Oklahoma City freeways
• Good contacts, poor data

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Some Preliminary Results

• High Salt
• 86 of steel beam bridges replaced
• Avg. Life lt 29.6 years
• No Salt
• 0 of steel beam bridges replaced
• Avg. Life gt35 years

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Problems

• We dont know how long the no-salt bridges will
  last.
• Extrapolate to no-salt life expectancy

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Next Quarter Plans

• Complete analysis for 3 target states
• Add 1 more high-salt and one more low-salt
  state to study
• Begin to accumulate salt-use and maintenance
  data