Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Long Lived Bridges:
Recent Developments in the United States
and Future Research Needs
Joseph L. Hartmann, PhD, PE
Leader, Bridge Design and Construction Team
Office of Infrastructure R & D
Federal Highway Administration
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Presentation Topics
• Bridge Engineering Issues
• Selected Current FHWA Studies
• Other Research Needs
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Bridge Engineering Issues
• Our industry requires structures that are
– Durable
– Constructable
– Maintainable
– Inspectable
– Resilient to extreme events
– Easily adapted to changing demands
– INEXPENSIVE!
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Bridge Durability
• Decks
• Higher performance materials
– Corrosion/deterioration resistant
[materials/coatings]
– Crack/fracture resistant
– Fire resistant
– Impact resistant
• Improved design codes (performance-based?)
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Bridge Construction
• Fabrication/casting technology
• Construction QA/QC technologies
• Accelerated construction technologies
– Prefab systems and components
– Erection equipment to handle prefab
– Simpler foundations and substructures
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Bridge Maintenance and Preservation
• Decks
• Joints
– Superstructure
– Bearings
– Substructure
• Foundations and Approach Slabs
– Scour
– Erosion/settlement
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Bridge Inspection and Evaluation
• Simple/hand-held tools
• Advanced NDE
• Structural monitoring (short and long-term)
• Non-accessible elements/components
• Load capacity evaluation/rating tools
• Turning inspection data into useful decision-
making information
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Extreme Events
• Earthquake
• Flood
• Wind
• Impact (vehicle, ship/barge)
• Fire
• Blast
• …..
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Adaptable to Change
• Traffic demands
• Climate change
• Age (repair, rehab)
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Overarching Issue…
Data Information
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Selected current FHWA projects that address
issues.
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
FHWA Research Mechanisms
• Contract R&D…consultants, universities,
others
• In-House FHWA Laboratories
– Structures
– Geotechnical
– Hydraulics
– Aerodynamics
– Non-Destructive Evaluation (NDE) Center
– Durability (Paint/Coatings/Corrosion)
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
UHPC for Modular Bridge Connections
SR 31 over Canandaigua Outlet
Lyons, New York
61 in. 6 in.
Closure Pour (UHPC)
Deck Bulb Tee Prestressed Girder
41 in.
6 in.
Closure Pour (UHPC)
Precast Deck Panel8 in.
96 in.
SR 23 over Otego Creek
Oneonta, New York
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
FHWA-AASHTO Joint Study (NCHRP 12-84)
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
I-35W Bridge
Collapse
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
I-35W Bridge Collapse
• Among the questions raised:
– Performance of gusset plates
– Gusset plate evaluation and rating
– Gusset plate inspection
[determination of corrosion or remaining section
of multiple plate systems]
**Design error…not fatigue, corrosion or inspection.
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Limit State Performance
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Phase 2 Test Matrix – Corroded Specimens
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Corrosion Between Multiple Plates
• Inaccessible; conventional NDE does not work
• Technologies being assessed include:
– Pocket UT (Ultrasonic Portable C-Scan Imaging
System)
– Phased Array Ultrasonic Testing
– Active IR Thermography
– Portable Radiography
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Corrosion in Concrete Bridges
• NDE methods being assessed:
– Microwave (Thermo) Reflectometry
– Ground Penetrating Radar (GPR)
– Ultrasonic Echo / Impact Echo
– Infrared (IR)
– Half Cell / Linear Polarization
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
NDE Technologies for Hidden Wire Corrosion
NDE technologies are being
evaluated for corrosion detection
in PT external tendons, stay
cables, and suspension cables
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Long-Term Bridge Performance Program
(LTBPP)
• Designated in “SAFETEA-LU” surface
transportation authorization legislation (August
2005)
• Intended as a long-term research effort to
improve our knowledge of bridge performance
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Tools for
Program Objectives
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
• Detailed inspection, periodic evaluation and
monitoring by taking advantage of sensor
technology
• Representative sample of “work-horse” highway
bridges
• Forensic autopsies of decommissioned bridges
• Leverage accelerated testing when possible
Program Approach
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
• Sept. 2009 – Sept. 2011
• Detailed inspection and
monitoring of 7 bridges
• Validate protocols
and processes
• Coordinate with SHAs
for field investigation
Pilot Bridge Location
Pilot Bridge Study
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
LTBPP Pilot Bridges
• Constructed in 1976
• Single span AASHTO beams with integral abutment
• CIP concrete deck with asphalt overlay and membrane
• AADT of 22,250 with 29% truck traffic
• Constructed in 1979
• Continuous built-up steel girder
• CIP concrete deck
• AADT of 16,500 with 6% truck
traffic
Virginia Utah
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
LTBPP Pilot Bridges
• Constructed in 1969
• Single span multi-beam steel girder bridge
• CIP concrete deck, stay-in-place forms
• AADT of 25,000
• Constructed in 1975
• 2-span Pre-stressed post-tensioned
continuous CIP Box Girder bridge
• AADT of 24,500 with 21% trucks
California New Jersey
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Activity VA UT CA NJ MN NY FL
Bridge Selection Done Done Done Done Underway Underway TBD
Finite Element Model Done Done Done Done Future * Future * Future *
Live Load Testing Done Done Done Done Future * Future * Future *
Visual Inspection Done Done Done Done Future * Future * Future *
NDE Deck Survey Done Done Done Done Future * Future * Future *
Coring & Physical
TestingDone Done Done Done Future * Future * Future *
Analysis of Results Underway Underway Underway Underway Future * Future * Future *
* Anticipated
Completion date:
03/31/2011
LTBPP Pilot Study Status
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
• Improved knowledge of State maintenance effectiveness
• Demonstration of effectiveness of sensor technology in
bridge inspection/condition assessment
• Improved bridge life-cycle cost analysis and deterioration
prediction
• Basis for implementation of performance based design
• Protocols for load rating based on structural monitoring
• Foster the next generation of bridge and asset
management systems and tools
Anticipated Impacts of a 20+ Year Program
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Continuing Research Needs
• Risk-based Inspection Approaches
• Inaccessible Component Inspection Technology
• Remote Inspection and Visualization
• Sensors and Systems
– Short-term performance evaluation
– Long-term performance monitoring
– Motorist warning
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
• Rapid Load Capacity Assessment
• Underwater Inspection/Imaging
• SHM Data Fusion and Knowledge Tools
• Fire-resistant materials
• Improved welding processes (speed, quality,
consumables)
• In-situ stress/strain measurement
More Needs…
TURNER-FAIRBANK HIGHWAY RESEARCH CENTER
Thank you…questions?