General View                                                                 Typical Cross-Section Geometry Of The Bridge

Elevation View Of The Portion Of The Eastbound Bridge

Bridge Substructure

Locations Of Accelerometers Used for (Refined) Experimental Measurements

First Stage Of Damage Two-Foot Web
Cut Centered at Girder Mid-Span

Second Stage Of Damage Six-Foot Cut From The Center Of The Web To The Bottom Flange at Girder Mid-Span

Third Stage Of Damage Six Foot Cut In The Web Plus Half of Bottom Flange Cut at Girder Mid-Span

Fourth Stage Of Damage Six-Foot Cut In The Web Plus Full Bottom Flange Cut at Girder Mid-Span

 

• For All Investigated Damage Scenarios of The I-40 Bridge, Detection was reliably achieved
• Distinctive Pattern Exists For The New Damage-Parameter Experimental Distributions With:
  • Persistently-Monotonic Abrupt Changes With Increased Damage
  • Equal Changes In Crack Sizes Producing Disproportionate Change In Damage Index

 

• Demonstrated Feasibility Of Scheme With Modest Demands For Input/Output Signal Measurements
• A Single Flexural Mode Processing For Each Case Proved Sufficient For Detection

Advantages Of Proposed NDE Scheme:

• Sound Theoretical Basis
• “Modest” System / Operation Requirements:
  • Strain Sensors
  • Rotation Sensors
  • Accelerometer (Dynamic)
• Direct Approach / Distinct Pattern-Easily Recognized<\LI>