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Precast/Prestressed Concrete Institute (PCI)
National Concrete Consortium San Antonio, Tx
April 1, 2009
Precast/Prestressed Concrete Institute (PCI)
National Concrete Consortium San Antonio, Tx
April 1, 2009 William Nickas, P.E.
Director, Transportation Systems
Precast/Prestressed Concrete Institute Chicago, IL
2
RapidApproaches
MinimalDisruption
SuccessfulRenewal
Long-LivedFacilities
To develop a consistent, systematic approach to performing highway renewal that
• is rapid • causes minimum
disruption• produces long-
lived facilities
Goal
3
TechnologyTechnology Project DeliveryProject Delivery
SuccessfulRenewal
Integrated approach
Concrete Bridges and the NBI dataConcrete Bridges and the NBI data
Post Tensioned Durability StrategiesPost Tensioned Durability Strategies
PCI Quality Systems & Plant CertificationPCI Quality Systems & Plant Certification
FHWA Long Term Bridge Program (LTBP)FHWA Long Term Bridge Program (LTBP)
Cooperative Agreement for PPCP with FHWACooperative Agreement for PPCP with FHWA
AgendaAgenda
A Report Card on Concrete and Bridge Longevity
Data Reduced and Charted by:Heinrich O. BonstedtExecutive DirectorPrestressed Concrete Association of Pennsylvania
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Data Source
The National Bridge Inventory December 2008
Prepared according to a Standard Recording and Coding Guide that covers over 115 items
“By having a complete and thorough inventory, an accurate report can be made to Congress” and it provides the data necessary to “produce Defense Bridge and Federal Emergency Management Agency (FEMA) reports.”
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Evaluation Objectives
Determine deficiency rates for bridgesEvaluate deficiency trendsCompare bridge material alternativesEstablish a basis for projections of service life expectancy
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Sources of Deficiencies
Super-structure conditionSub-structure conditionDeck conditionAppraisal Rating
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Concrete Observations
Deficiency rates for concrete bridges are decliningMarket share of concrete bridge material alternatives is increasingMore work is needed to refine projections of service life expectancy with current methods.
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Florida DOT efforts toward improving Post Tension Durability at UT, Austin ASBI Training April 2006 by William Nickas
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Pile Deterioration
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Pier Deterioration
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Leakage at Segment Joints
pci 30Failure of Tendon Anchorage Pour back
pci 31Boot Removed showing Corrosion
pci 33Wedge Assembly
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Borescope Inspection - Moderate
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Borescope Inspection - Bad
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Partial Grout
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85% of strength
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Cracked Ducts
PO
ST-T
EN
SIO
NIN
G S
TA
ND
AR
D D
ET
AIL
S
•Standardized Details with PCI
Proper Material is CriticalProper Material is Critical
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Pier 133 NB
SE Tendon
NE Tendon
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Field Book Notes
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New Grout Material Specification• Chloride Ion Limited .08% by weight (ASTM C1152)• Volume Change 0.0% @ 24 Hrs. (ASTM C1090)
<=0.3% @ 28 days• Compressive Strength >7,000 PSI (ASTM C942)• Initial Set Time Min. 3 hours (ASTM C953)
Max. 12 hours• Fluidity Test Immediately after mixing (ASTM C939)
30 minutes after mixing• Bleed @4 Hours 0% (ASTM C940)• Permeability @ 28 days Max 2500 Coulombs (ASTM 1202)
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New Type Low Bleed Grout 10 hours old…..No bleed void
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Example Post-Tensioning Tendon Classifications
Essential
87
109
654321
Critical
Very High
High
Moderate
P/C SBS External– EJ SpansP/C SBS External– Typical Spans
Drop in PT Girders; ¼ Point HingeP/C BC – Continuity at EJ
P/C BC – Anchor on FaceP/C BC – Anchor in BlisterP/C BC – Bottom ContinuityCIP Cantilever & ContinuityFlat Slab - TransverseP/C BC – Top Continuity
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FDOT Post-Tensioning Strategy
Anchor Protection
Fully Grouted TendonsMultiple Tendons Paths
Enhanced PT Systems
Watertight Bridges
FDOT PTStrategy
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Requirements
• 4 Levels of Protection• Semi Standard Details• Anchorages Sealed at all Times
Requirements
• Anchorage Accessibility• Low Point Injection• Semi-Standard Drawings• Certified Grouters and Inspectors• Controlled Rates of Grouting• Flow Rate Testing of Ejected Material• Inspect Voids and Secondary Grout
Requirements
• Pre-Approved PT Systems• Pre-Bagged Grout• Three-Level Continuous Protection• Plastic Ducts with Improved Cell Class• Positively Sealed Ducts• Permanent Plastic Anchor Caps• Pressure Testing
Requirements
• No Dry Joints• Pre-formed Tapered Holes• Drip Notches at Anchorages• Bottom Slab Drains• Sealed Surfaces of Secondary Pours• Wearing Surfaces for Ride not Protection• No Permanent Tensile Stresses
Flor
ida
PT S
trate
gy
Enhanced PT Systems
Fully Grouted Tendons
Watertight Bridges
Anchor Protection
Requirements
• Maximize Use of Smaller Tendons• No Impact Due to Loss of Critical Tendon• Compensation for Loss Due to Corrosion
Multiple Tendon Paths
A non-Florida Project
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Why not always use Plastic Duct ?Why not always use Plastic Duct ?
pci 57Mid-Bay Bridge
www.dot.state.fl.us/structures
Temporary Design Bulletin (Post-Tensioning Issues)
About PCIAbout PCI
• PCI is an international trade association and Technical Institute – Promotes technical understanding and use
of high-quality precast and prestressed concrete
– Full staff of technical and marketing specialists
About PCIAbout PCI
• Over 350 Producer Member plants – Architectural, structural, and specialty
precast concrete products and structures– Every U.S. PCI Producer Member plant
must be PCI Certified– PCI Membership is not required to be PCI
Certified– Over 80 Technical Committees
About PCIAbout PCI
• Approximately 200 Supplier Associate Members
• 100 Erector Associate Members – PCI Qualified/Certified Erector Program
• Over 1,300 Professional Members – Academics, design professionals,
and other industry stakeholders – Provide much of the technical
knowledge contained in PCI design guides and other technical publications
About PCIAbout PCI
PCI Publications• Design Manuals and Guidelines• Quality Control Manual• PCI Journal, Ascent, and Aspire
Magazines
About PCIAbout PCI
• Codes and Standards– PCI works very closely with code bodies,
such as ACI, ICC, ASTM, AASHTO, etc.
• Industry Events– PCI works with FHWA in producing the
National Bridge Conference
About PCIAbout PCI
• Research & Development– DSDM Seismic Project– FHWA Precast Pavement
Project
TeTeTe
Side Walls
Load Cell
Floor Diaphragms
Shake Table
ReactionWall
Steel Base withCantilever Outriggers
6 ft – 6 in
These concepts and ideas are early findings sharedby the team during the 2009 TRB Briefing of FHWAand the Researchers.
Program manager is:Dr. Hamid Ghasemi (202-493-3042)[email protected]
He is the official POC for information regarding the program, rather than Rutgers.
In addition for information regarding the LTBP pilot program,they can contact:John Penrod (202-493-3051)[email protected],He is a member of the LTBP project team and will be managing the pilot program activities.
Team Organization
Roadmap: First Five Years
Process and Timeline
Defining and Measuring Bridge Performance
What Does Bridge Performance Mean?
•
Is it a measure of cost?
•
Is it a measure of condition?
•
Is it a measure of traffic service?
•
Is it a measure of load capacity/safety?
•
And what purpose will measuring bridge
performance
serve?
Defining and Measuring Bridge Performance
Defining and Measuring Bridge Performance
Study Goal
Develop Performance Measures that:
•
Define bridge performance in terms of things we
can measure•
Determine cost effective design/maintenance
strategies•
Evaluate serviceability and durability
•
Establish accurate traffic safety evaluation
•
Provide an accurate measure of load capacity
Defining and Measuring Bridge Performance
Factors in the Difficulties of Measuring Bridge Performance
•
Bridge Inspection Policy
•
QA/QC
•
Personnel / Inspector Qualifications and
Training•
Programmatic Considerations
•
Bridge Load Rating
•
Documentation
•
New Technologies
•
Bridge Deterioration Database
•
Communications
•
Research Needs
Defining and Measuring Bridge Performance
ASCE/SEI White Paper Bridge Inspection and Rating
2007 Structurally Deficient NHS Bridges
Defining and Measuring Bridge Performance
Objectives of NDE Performance Monitoring
Ultimate Objectives
Develop and implement plan for high quality quantitative data collection using NDE technologies that will:
»
Enable
condition monitoring that will be objective and linked to bridge performance measures
»
Improve
understanding of deterioration processes and bridge performance
»
Advance
predictive methods and bridge management practices
Bridge Monitoring: NDE
Serviceability: Degradation and Improvement
A-$2 B-$10
C-$50
D-$100
Age
Ser
vice
abili
ty
Cost to improve serviceability:A - Initial ConstructionB - Preventive MaintenanceC - Corrective MaintenanceD - Reconstruction
LTBP Monitoring
Bridge Monitoring: NDE
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Precast/Prestressed Concrete InstitutePrecast/Prestressed Concrete Institute(PCI)(PCI)
Federal Highway AdministrationFederal Highway Administration(FHWA)(FHWA)
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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PRECASTING PLANTSPRECASTING PLANTS
A A manufacturing operationmanufacturing operation……
……not offnot off--site construction!site construction!
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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PCIPCI--FHWA Cooperative Agreement FHWA Cooperative Agreement
““Advancement of Precast Prestressed Advancement of Precast Prestressed Concrete Pavement SystemConcrete Pavement System
throughthrough Technology TransferTechnology Transfer
andand Development of Industry GuidanceDevelopment of Industry Guidance
forfor Design and EngineeringDesign and Engineering””
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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PCIPCI--FHWA Cooperative Agreement FHWA Cooperative Agreement
•• NonNon--ProprietaryProprietary•• Manufactured in PCIManufactured in PCI--Certified Plants Certified Plants •• ““Precast Prestressed Concrete PavementsPrecast Prestressed Concrete Pavements””
(PPCP)(PPCP)
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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What is PPCP?What is PPCP?
–– 22--way way prestressingprestressing–– Combination of Combination of pretensioningpretensioning/post/post--tensioningtensioning–– OrOr 22--way postway post--tensioningtensioning–– Bonded/grouted PBonded/grouted P--T systemT system
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Typical PPCP PanelTypical PPCP Panel
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Typical PPCP Panel LayoutTypical PPCP Panel Layout
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Typical PPCP Panel LayoutTypical PPCP Panel Layout
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Typical PPCP Panel LayoutTypical PPCP Panel Layout
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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BenefitsBenefits
WHY PRESTRESSED CONCRETE?WHY PRESTRESSED CONCRETE?–– Reduces/eliminates slab cracking (maintenance)Reduces/eliminates slab cracking (maintenance)–– Reduced number of joints Reduced number of joints
(maintenance/smoothness)(maintenance/smoothness)–– Reduced Slab Thickness (8Reduced Slab Thickness (8”” vs. 12vs. 12””) )
•• Material savingsMaterial savings•• Allows for replacement of pavement inAllows for replacement of pavement in--kindkind
–– Ability to span voids/unsound support layersAbility to span voids/unsound support layers–– Proven LongProven Long--Term Performance Term Performance
•• 66”” CIP postCIP post--tensioned pavement constructed in 1985 tensioned pavement constructed in 1985 (near West, Texas)(near West, Texas)
•• Virtually no maintenance in 23 yearsVirtually no maintenance in 23 years
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Picture of Connection detailsPicture of Connection details
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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Getting ready to post tension the PC pavementGetting ready to post tension the PC pavement
Precast Concrete PavementsPrecast Concrete Pavementspcipcipcipci
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PCIPCI--FHWA Cooperative Agreement FHWA Cooperative Agreement
Cooperative Effort to Engage Industry and AgenciesCooperative Effort to Engage Industry and Agencies
Concluding and Departing Thoughts Concluding and Departing Thoughts
• Manufactured Concrete offers further enhancements opportunities when used properly in routine projects and ABC
• Higher Concrete strengths and innovative engineering is extending span ranges for concrete,
• We all as an industry should guard against New Specifications and code changes allowing unintended consequences,
• Loads, Stresses, and Environment all contribute to the total Durability of the Concrete not just the mix design
Dr. Galambos writes DEFINITION: RESEARCH
Dr. Galambos writes DEFINITION: RESEARCH
• THE ACTIVITY THAT CONNECTS THEORY WITH PRACTICE
• COMPUTATION METHODS
• PHYSICAL AND COMPUTATIONAL EXPERIMENTS
• ORGANIZATION OF DATA AND DESIGN ACTIVITIES
• ETC.
Dr. Galambos writes FEATURES OF STRUCTURAL DESIGN
CREATION OF A STRUCTURE THAT WILL
Dr. Galambos writes FEATURES OF STRUCTURAL DESIGN
CREATION OF A STRUCTURE THAT WILL
• PERFORM SATISFACTORILY DURING ITS INTENDED LIFETIME
• NOT COLLAPSE OR EXPERIENCE EXCESSIVE DAMAGE DURING ITS INTENDED LIFETIME
• BE ECONOMICAL TO DESIGN, BUILD AND MAINTAIN
• SERVICEABILITY
• SAFETY
• ECONOMY
Dr. Galambos write EXPECTATIONS FROM STRUCTURAL
DESIGN
Dr. Galambos write EXPECTATIONS FROM STRUCTURAL
DESIGN• GENERAL PUBLIC
• STRUCTURAL ENGINEER
• BUILDING AUTHORITY
• CODE COMMITTEE
• STRUCTURE IS UNCONDITIONALLY SAFE AND RIGID
• SAFETY, SERVICEABILITY, ECONOMY DURING INTENDED LIFETIME WHEN USED FOR PLANNED FUNCTION
• CODE REQUIREMENTS MUST BE MET
• CHANCE OF EXCEEDING A LIMIT STATE DURING
Dr. Galambos writes HOW TO ATTAIN SAFE
STRUCTURAL DESIGNS?
Dr. Galambos writes HOW TO ATTAIN SAFE
STRUCTURAL DESIGNS?• MINIMIZE HUMAN
ERROR
• QUALITY CONTROL
• ENSURE THAT CHANCE OF EXCEEDING LIMIT STATE IS ACCEPTABLY SMALL
• LOAD STANDARDS AND DESIGN CODES
REQUIREMENTS FOR THE DESIGN OF THE INDIVIDUAL STRUCTURE
APPLICABLE LEGAL BUILDING CODES
MODEL BUILDING CODES
MATERIAL CODES, LOAD STANDARDS,DESIGN SPECIFICATIONS
Dr. Galambos writesPYRAMID OF DESIGN REQUIREMENTS
Concluding and Departing Thoughts Concluding and Departing Thoughts
• Structural Engineering Congress in London in 1960’s….
• “Structural Engineering is the art of assembling materials we do not fully understand, to resist loads that we cannot accurately estimate, in a fashion that the general public does not understand the extent of our ignorance”
Concrete BridgesConcrete BridgesAnd other Transportation Delivery
Opportunities
THANK YOU!
And other Transportation Delivery Opportunities
THANK YOU!
William Nickas, P.E.Director, Transportation [email protected]