Transcript SHRP2: First Demo Project, Keg Creek, Iowa

SHRP 2 - FIRST DEMO PROJECT
KEG CREEK, IOWA
R04 – “BRIDGE DESIGNS FOR RAPID
RENEWAL”
Sandra Larson, P.E.
Iowa Department of Transportation
Research and Technology Bureau Director
[email protected]
RAC/TRB 2012 Annual Meeting
Burlington, VT
THREE MESSAGES
2
SHRP 2 Overall Plan - Leading to
Implementation of Products
Accelerated Bridge Construction
(ABC) Background
Iowa’s SHRP 2 Demo Project
Details– Keg Creek
Thanks to Neil Pedersen (SHRP 2) and Ahmad AbuHawash (Iowa DOT) for slide information
SHRP 2 (Second Strategic
Highway Research
Program)
Overall Plan - Leading to
Implementation of Products
SHRP 2 PLAN
4
Research (2005 - 2013)
• 100+ research projects
• Administered by TRB
Development (Now through 2015)
• Pilots and demonstrations
• Testing and refinement of products emerging from research
Implementation (2012 - forward)
• Partner agencies prioritize products for implementation
• Selected products systematically integrated into current transportation
practices
Keg Creek - SHRP 2 Demo Project
5
SHRP2 funds:
–
–
–
–
$250,000 for construction
Assistance with design of bridge through consultant
Assistance with project details and problem solving
Held showcase, produced video
HFL funds: $600,000 or 20% of construction cost
Iowa DOT research and construction funds, staff
time, commitment of resources
Iowa State University research testing
SHRP 2 Focus Areas
Safety: fostering safer driving through analysis of
driver, roadway and vehicle factors in crashes,
near crashes, and ordinary driving
Renewal: maintaining and repairing the
deteriorating infrastructure using already-available
resources
Reliability: managing non-recurring events to
create more predictable travel times
Capacity: building a highway system that creates
minimum disruption and meets the environmental,
and economic needs of the community.
6
SHRP 2 - Definition of Success
5-6 States adopt as standard
practice
Additional states follow the lead
AASHTO and FHWA provide
continuing support
Private sector buy-in
Positive impact on practice
Cost-effective use of products
7
Accelerated Bridge
Construction (ABC)
in Iowa
Iowa DOT ABC Deployment
Strategy – past several years
9
Develop skills and design details through
demonstration projects (IBRD, HfL, SHRP2, ..)
Invest in research and include laboratory and
field testing to confirm constructability and
performance.
Participate in national pooled fund studies
Involve local construction industry and hold
ABC workshops.
Develop policies for ABC
ABC/PBES
Prefabricated Bridge Elements and
Systems (PBES): it is a strategy to
accelerate bridge construction that
employs prefabricated individual Elements
such as beam, deck, abutment footing,
pier column, pier cap, etc. Or entire
superstructure System that is assembled
off-site and moved into place.
Why use ABC?
– To deal with schedule constraints
Limited time-window due to special events
Emergency replacement due to natural disasters,
accidents, or intentional acts
– To minimize impact on local traffic
Access to business
Commuters
Essential services
– To deal with the unavailability of suitable
detour
ABC: Benefits
Reduced public inconvenience
Improved public perception
Improved road users and workers safety
Reduce negative economic impact on
local businesses
Perhaps improve the durability of the
structure
ABC: Disadvantages
Substantial increase in construction cost:
fewer bridge replacements
Contractors are generally uncomfortable
with the PBES concept: higher cost
Requires the development of new design
standards and specifications: higher
design cost
Case Study: Keg Creek
Lessons Learned
SHRP 2 Program
First Demo Project
Keg Creek Bridge
- IT’S A BIG DEAL 15
Iowa DOT wins America’s Transportation
Award, announced July 18 2012:
The Iowa DOT received an award in the “Best
Use of Innovation” category for the U.S. 6 bridge
over Keg Creek in Pottawattamie County.
This bridge was completely prefabricated off-site
and then assembled at the construction site using
an accelerated bridge construction method.
Utilizing this approach, the road was closed for
only two weeks.
Background
SHRP2 – R04 Research Team needed to
demonstrate ABC design concept for
typical multi-span stream crossings – a
common rural bridge replacement
Proposed a demonstration project in Iowa
Successful project may pave the way for
developing national ABC standards
A bridge on US 6 over Keg Creek in
Pottawattamie County met the objectives
EXISTING BRIDGE
180’ x 28’-0 Continuous concrete
girder bridge
Built in 1953
3 spans
53’6”,73’,53’6”
Moderate sized,
typical rural
crossing
Small,
meandering
stream
Narrow bridge
width on primary
road system
Sufficiency rating
33
Keg Creek - Project Data
Design: HNTB
Testing: ISU
Bridge Construction Cost: $2,658,823
Unit cost: $231 per sq.ft. ($124 estimated for
conventional in Iowa)
Incentive/Disincentive : $22,000 per day
SHRP2 funds: $250,000
HFL funds: $600,000 or 20% of cost
New bridge: 204’-6 x 44’-0 Prefabricated Steel
Modular Superstructure on Precast Substructure
supported on Drilled Shafts.
Why Keg Creek?
Typical rural, moderate size stream
crossing in Iowa. Indicative of many
bridges throughout the mid-west and
country. SHRP2 looking to standardize
ABC design plans.
Detour: 22 mile detour less desirable for
traveling public over 4 to 6 month period
versus 2 week ABC period.
Schedule: already programmed for 2011
construction.
Iowa Bridge Farm (Phase 1)
Precast Substructure
Components Casting (Phase 1)
Superstructure
Modules –
Structural Steel
Assembly (Phase 1)
Superstructure
Modules – Deck
Forming (Phase 1)
Deck
Concrete
Placement
(Phase 1)
Drilled Shaft
Construction
(Phase 1)
26 kips
Abutment
/ Wing
Erection
93 kips
Column Assembly
52
kips
Bedding and Coupler Grouting
Cap Beam Assembly
168 kips
Superstructure Module Transport
102-112 kips
69-80 kips
Module Assembly
Module Assembly
Final Module Placement
Flooded Backfill System
Precast Approach Preparation
35 kips
Precast Approach Slab
Placement
31-37 kips
UHPC Placement
Completed Bridge
Conclusions
R04 - ABC design concept was successfully
demonstrated, but there were some challenges
along the way.
Post construction review identified problem areas,
as expected, and provided recommendations for
improvements which will be documented in the final
report.
As the result of this project (and other past ABC
projects), Iowa DOT gained a better understanding
of risks and benefits associated with ABC and is
developing ABC policy and planning more ABC
bridges.
Project
Website
http://www.iowadot.gov/us6KegCreek/
Questions?
Thanks to:
Neil Pedersen, SHRP 2
Ahmad Abu-Hawash, Iowa DOT
For slide material