Accelerated Bridge Construction 2010, a presentation on advanced bridge building techniques by the Utah Department of Transportation

1. ABC By 2010
UTAH
ABC by 2010
Department of Transportation
ACCELERATED
• UDOT goals
BRIDGE CONSTRUCTION BY 2010 – Accelerated Bridge Construction
• Standard practice by 2010
How have we done? • What was needed?
Fred Doehring
– Methods of construction
UDOT Structures
– Standard details
– Commitment to a program
Vision for “Family” of ABC Methods ABC Phase 1
• Early implementation of ABC
Accelerated – Scanning Tours
Bridge
Construction • Looked at what other states were doing
– Workshops held
• Brought all stakeholders together
Precast Modular Structure Accelerated Fast Track
Concrete
Elements
Construction
Large Prefab.
Placement
Methods
Geotech
Work
Contracting
CMGC
• Identified what was needed
Components Design/Build
Prefabricated
Components
SPMT
Sliding
Geofoam
• Prioritized needs
• Looked at several specific pilot projects
ABC Phase 1 ABC Methods Used
• Results of Phase 1 work
– Several key standards were • Precast Deck Panels
developed • Voided Slabs
• Precast Full Depth Deck Panels
• Precast Substructures
• Manual on Self Propelled Modular
Transporters (SPMT’s) – Abutments and Bent Caps
• Development of specifications • Precast Superstructures
and manuals for each
– Crane, Sliding, and SPMT
• Several pilot projects initiated and
built
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2. ABC By 2010
Precast Deck Panels - Full Depth Precast Deck Panels - Full Depth
Precast Deck Panels - Full Depth Precast Deck Panels - Full Depth
Precast Deck Panels - Full Depth Precast Deck Panels - Full Depth
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3. ABC By 2010
Precast Deck Panels - Full Depth Precast Deck Panels - Full Depth
Voided Slabs Voided Slabs
Precast Substructure Precast Substructure
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4. ABC By 2010
Precast Substructure Precast Substructure
Precast Superstructure - Crane Precast Superstructure - Crane
Precast Superstructure - Sliding Precast Superstructure - Sliding
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5. ABC By 2010
Precast Superstructure - SPMT Precast Superstructure - SPMT
Precast Superstructure - SPMT Precast Superstructure - SPMT
Precast Superstructure - SPMT Precast Superstructure - SPMT
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6. ABC By 2010
Precast Superstructure - SPMT Precast Superstructure - SPMT
UTAH
ABC Phase 2
Department of Transportation
• Standardized the remainder of prefabricated
ACCELERATED element types
BRIDGE CONSTRUCTION BY 2010
• Developed details for:
– Precast substructures
• Piers, Abutments, walls, culverts
Where are we going? – Precast Approach slabs
– Precast Girders
• Pre-tensioned Bulb Tees
Michael Culmo
• Post-Tensioned Bulb Tees
CME Associates, Inc.
• Deck Bulb Tees
• Developed Specifications and Manuals
• Workshops were held for industry input
Connections with Grouted Splice Couplers
ABC Phase 2
• Emulates a reinforcing steel lap splice
• Other work completed in Phase 2 • Used in precast parking garages and
– Reviewed computer monitoring data from first stadiums and bridges
round of SPMT bridge moves • New seismic research coming
– Refined Phase 1 work based on lessons
learned in construction
• Deck Panel standards and specifications
• SPMT Manuals
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7. ABC By 2010
Connections with Grouted Splice Couplers
Typical Connection Details
Installation video on Youtube
Search “Georgia Bridge Pier” Column or wall panel
to footing connection
Typical Connection Details Current Typical Details
• Single column hammerhead
Column to cap
connection • Two column bent
• Three column bent
Current Typical Details Current Typical Details
Columns Footings
• Rectangular are possible, • Full Precast
but not preferred
• Round columns are difficult – For smaller footings
to precast
– Must be cast vertically
• Use Hexagonal or
octagonal shape
– Can be cast on side
(one side open)
Shim and grout under footing
through ports in footing
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8. ABC By 2010
Current Typical Details Current Typical Details
Footings Pile supported
• Partial Precast footings
– For larger footings • Use corrugated
– Precast designed to support
DL of bridge
pipe forms
– CIP extensions designed for • Used for integral
other loads abutment stems
Precast Portion
also
CIP Extension
Shim and grout under footing
through ports in footing
Pretensioned Bulb Tee Girders Pretensioned Deck Bulb Tee Girders
Post-tensioned Bulb Tee Girders Integral Abutment Details
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9. ABC By 2010
Cantilever Abutments and Walls Stage 1
• Use corrugated pipes in stems to reduce weight
– To be filled with concrete in the field
– Reduces the number of pieces
1. Drive Piles
Stage 2 Stage 3
1. Install pier wall panels. (day 4)
2. Connect to footing via grouted
1. Place footings over pile and set
splice couplers (day 4)
to grade and alignment (day 1)
3. Fill voids with concrete to within
2. Cast concrete in voids around
3 feet of top (day 5)
piles (day 1)
4. Install rebar cage in top of voids
3. Cast concrete between footings
extending 2 feet above (day 5)
if required (day 2)
5. Joints between may be grouted
or left dry
Stage 4 Final Construction
1. Install pier cap, set to grade
(day 6)
2. Pour concrete through ports
to fill voids and make
connection (day 7)
3. Install precast beam seats
(day 7)
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10. ABC By 2010
Box Culverts Tolerances
• Precast boxes, aprons, and walls
• Tolerance details developed for all critical
elements
• Based on PCI Tolerance manual
– MNL-135-00
Tolerance Details Tolerance Details
Splice couplers Columns
Precast Full Depth Deck Panels Precast Full Depth Deck Panels
• First Generation Standards completed in • Phase 2 Modifications
Phase 1 UDOT ABC Program – Use Longitudinal Post-Tensioning to Connect Panels
• AASHTO Code Recommendation
• More than 15 project built to date • Better performance over time (no leakage through joints)
• Costs are coming down – Use multi-strand PT systems
• Developed for slabs
• Welded plate details are not desirable • More Flexible
– Time – Allow blind pockets for shear stud connection
• Based on recent research
– Leakage issues at joints
– Allow skewed deck panels (up to 15 degrees)
• There is new technology in the market
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11. ABC By 2010
Precast Full Depth Deck Panels Blind Pocket Project – Texas DOT
• Recommended Post-tensioning System
– Multi-strand deck PT systems
– Developed specifically for decks (thin anchorage)
– Used by other states
– Recommend the use of less than maximum amount
of PT allowed in the ducts (4-0.5” strand)
UDOT Blind Pocket Details
Schematic Construction Details
2 Span Bridge using UDOT Standards
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12. ABC By 2010
Excavate and Install Piles Install Abutment Stem and Footings
Typical 2 Span Bridge Typical 2 Span Bridge
Install Pier Columns Install Pier Cap and Wingwalls
Fill Voids in Abutment Stems Cast Footing Closure Pour
Typical 2 Span Bridge Typical 2 Span Bridge
Erect Girders Install Backwalls and Sleeper Slabs
Typical 2 Span Bridge Typical 2 Span Bridge
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13. ABC By 2010
Install Deck Panels and Approach Slabs Cast Deck and Approach Slab Closure Pours
Typical 2 Span Bridge Typical 2 Span Bridge
Construction Roadway Approaches Bridge Monitoring (TAC)
• Volunteer group of key stakeholders
– UDOT
– Design Consultants
– Contractors
– Industry Representatives
• Charged with review of data and
recommendations for future SPMT bridge
moves
• Used computer monitoring data from 2008
Typical 2 Span Bridge
Bridge Monitoring (TAC) Bridge Monitoring (TAC)
• Data retrieved Temperature Strain
– Mostly strain data (deck, girders)
– Layouts were similar on each bridge
Dynamic Strain
– Used to study the stresses within the bridge during:
• Lifting
• Moving
Lifting Strain
• Placement
• Utah State University (USU)
– Brought in to analyze and disseminate the data
– With input from the TAC Typical Data
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14. ABC By 2010
Bridge Monitoring (TAC) SPMT Manual Revisions
• Final Findings and Recommendations • Build on knowledge gained in 2008
– Lifting stresses are very significant
• Supporting the deck at the lift points eliminated most deck cracking • No major changes
• Lift bridge closer to ends (0.2L or less)
• Lightweight concrete in the deck helps to reduce deck cracking, and
• Define roles of project participants
overall lift weight
• Written to fit in with the UDOT Design
– Dynamic effects can be approximated by increasing dead load
by 15% Network
• Starting and stopping of SPMT’s
• Traversing bumps during the move
– 3d Analysis is needed to estimate lifting stresses if a flexible
carrying beam is used
– Recommended future gaging locations
SPMT Lifting Methods Lessons Learned
• Study of Performance of ABC Bridges
• Bridge Types Studied
– Full Depth Deck Panels with welded tie connections
(6)
– Full Depth Deck Panels with Post-Tensioning (2)
– Precast Parapets integral with deck (5)
– SPMT Bridge Moves (9)
• Neg. DL moment on girder • Neg. DL moment on – Precast Abutments (2)
• May be a problem with composite section
prestressed girders • Significant deck cracking is – Precast Piers (2)
• Light weight concrete could possible
help • Light weight concrete could
• Inspections took place in May, 2009
• Little or no deck cracking help
• Deck is pre-compressed in
final condition
Lessons Learned Lessons Learned
Project locations • Purpose of the study
Milepost 200 on Route 6
not shown – Investigate the performance of each
component type
– What is performing well and what is not
– Not intended to critique past designs
• Most of these bridges were designed prior to
development of standards
• Many were designed as short term fixes prior to full
replacement in the near future (10-25 years)
– Goal: Continuous Improvement of Quality
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15. ABC By 2010
Lessons Learned Lessons Learned
• Welded Tie Connections • Welded Tie Connections
– Joint Leakage is widespread
– Shear transfer is still working
– Composite connection is good
Lessons Learned Lessons Learned
• Welded Tie • Welded Tie Connections
Connections
Lessons Learned Lessons Learned
• Post Tensioned Connections • Post Tensioned
– 3 span continuous bridge Connections
– No Joint Leakage
– Even in negative
moment areas
Underside of deck
I-215 at 3900 South
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16. ABC By 2010
Other Long Term Performance Information Project Information
• Curved structure (straight beams)
• I-84/Route 8 Interchange –Waterbury, CT • 6 Span bridge with continuous spans
• Single lane
• Prestressed transversely and post tensioned
longitudinally
• Details similar to UDOT
• 42 Day construction
• No construction problems
• Built in 1991
After 18 years of service After 18 years of service
• Excellent condition
• Used membrane waterproofing and Asphalt Wearing
surface
• No leakage through joints
Another long term example project Lessons Learned
Route 8 Viaduct, Seymour, CT • Precast parapets integral with precast
• 2 Curved structures decks
• Over 50 spans (all simple spans) – Most are good
• Prestressed and post tensioned – Problem with panels cast with 2 parapets
• Weekend closures only
• No transverse adjustment during installation
• Old deck removed on Friday night
• New deck erected on Saturday
morning
• Post tensioned on Saturday night
• Grouting on Sunday morning
• Open to traffic Sunday night
• Asphalt wearing surface with
waterproofing membrane
• In service for 15 years
• Excellent condition
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17. ABC By 2010
Lessons Learned Lessons Learned
• Precast Abutments
– Few have been built
• Horizontal joints (Lego bridges)
• None built to new standards yet
• There were significant fit-up
problems on one bridge
– Can be resolved with
appropriate casting tolerances
• Performing well
Lessons Learned Lessons Learned
• Precast Piers
– Few have been built
• None built to new standards yet
– One is similar
• Construction went well
• Performing well
Lessons Learned Lessons Learned
• SPMT Bridge Moves
– Deck cracking is common
– Exceptions:
• Bridges cast while supported at lift points
• Lightweight Concrete Deck
– Some leakage through cracks
– Performing well
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18. ABC By 2010
Lessons Learned Lessons Learned
Lessons Learned Lessons Learned
• Cast-in-place closure pours
– Some have significant shrinkage
cracks
• Restraint of adjacent panels
• Some leakage through cracks
Lessons Learned Lessons Learned
• Shear Connector Pockets
– Several have minor leakage
around pockets (not all)
• Shrinkage of Grout
• Blind pockets should alleviate this
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19. ABC By 2010
Lessons Learned Lessons Learned
• Recommendations
– Full Depth Deck Panels
• Eliminate welded tie detail
• Always use post-tensioning
• Use blind pocket detail for shear connectors
• New Standards address these recommendations
Lessons Learned Lessons Learned
• Recommendations • Recommendations
– Precast integral parapets – Precast Abutments and Piers
• Do not use 2 per panel • Use vertical joints in abutment stems and wall
stems
– Use a longitudinal closure pour in deck to allow for
– Allows for easier fit-up in the field
adjustment in the field
• No problems noted with pier construction
– Cast one or both in the field behind temp. barriers
• New Standards address these recommendations
Lessons Learned Lessons Learned
• SPMT Moves • Other general recommendations
– TAC Committee work verifies issues found in – Overlays
the field • Consider thicker overlay with a quality
• Pick bridges closer to ends waterproofing membrane
• If possible, support girders at lift points during – European and East Coast Systems
deck casting – CME recommendation, not UDOT policy
• Investigate the use of lightweight concrete to – Closure Pours
reduce deck and girder stresses • Use a better high early strength concrete mix
• New SPMT Manual will address these – Shrinkage compensating mixes
recommendations – NY State mix is being investigated
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20. ABC By 2010
Where are we going? Where are we going?
• UDOT Themes • Implementation of Phase 2 Standards
– Accelerate Delivery – Training
• Design and Construction • Designers
– Decrease MOT • Construction Inspectors
• Reduce User Costs and impact to society • Bridge Inspectors
– Encourage Innovation • Bridge Maintenance Personnel
– Get a good price – On-call technical support
Where are we going? Where are we going?
• Manuals • Continue to monitor progress
– Develop a Bridge Design Manual – Annual inspection of ABC Bridges
– New SPMT design guide to be issued – Address issues as they arise
• Lightweight Concrete • Goal:
– SPMT Decks (minimize deck cracking) Continuous Improvement
– Substructure Elements (reduce shipping and
handling costs)
Questions? Testing data
This presentation will
be posted on the
UDOT website
Grouted Splice coupler @ end of column
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21. ABC By 2010
Testing data
Control Column w/o Grouted Splice Coupler
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