Title: Innovative Bridge Designs for Rapid Renewal
1Innovative Bridge Designs for Rapid Renewal
- Transportation Research Board SHRP2 - Project R04
HNTB Corporation Iowa State University, Ames,
IA Structural Engineering Associates, San
Antonio, TX Nyleve Bridge, Emmaus, PA Walsh
Construction, Chicago, IL
2Major Questions
- How do we construct bridges quicker?
- How do we make them durable for 75 100 years?
- What technical issues are in the way?
- What deployment issues are in the way?
3Owner Initiatives
4Owner Initiatives
- R04 Findings Major Themes
- Strong impetus to use ABC
- Support (real or perceived) is strong at most
levels - Reluctant agencies list cost as the main
impediment - ABC, when used, has a remarkable satisfaction
rate - DB, AB and ID contracts most common
5Owner Initiatives
- Project Survey Main Themes
- Common reasons traffic and worker/public safety
- Few agencies have an ABC process
- Reasons for not employing ABC
- Requires more research
- Requires institutional change
- 5 agencies provided specifics on ABC projects
- User costs only considered to be real costs by 1
in 5 DOTs - Benefits considered to outweigh costs by all 5
DOTs
6Owner Initiatives
- Many Flavors of ABC
- Florida
- Several SPMT projects completed more planned
- Some use of precast pier construction
- Texas
- Significant use of prefabricated substructures
- Use of U-beams for rapid superstructure erection
- Utah
- Developing a standard agency policy centered
around rapid replacement - North Carolina
- Creation of Alternative Delivery Unit
7Project Procurement and Contracting
8Innovative Contracting
- UDOT CMGC
- Owner hires the engineer and contractor,
simultaneously, via separate contracts - NC DOT Washington Bypass
- Design Build Best Value
- Ministry of Transportation Model (Clyde Avenue)
- Only selected pre-qualified general contractors
invited to be bid - GCs required to submit credentials of one or
more heavy lifters for additional
prequalification.
9Innovative Contracting
- European Model (reference Freyssinet / Hebetec)
- Owner mandates specialty methods of erection
- Owner hires the specialty contractor or lifter
- Engineers required to design a compatible
solution - GC is required to construct the chosen solution
- Much less fear about engineer / contractor
interaction during design phases - User costs are highly valued
10Innovative Contracting
- Contractor Concerns
- If ABC shifts to large scale prefabrication and
use of specialty movers, what is the role of the
GC? - Has implications on profit and responsibility
- Current contracts involve expensive subs
- Lack of control of a large portion of the bid
price - Engineers should not dictate methods of
construction
11Innovative Projects / Construction Technologies
12Washington Bypass
Pictures from Flatiron Construction
13TxDOTPre-Topped U Beams
- 115 ft span capability depth / span 36
- With 4 c.i.p. topping and exterior barriers,
segment weight is 150 tons - Contractor places 2 spans per night
14Gantry Beam Erection
15Gantry Beam Erection
16FreyssinetAutoripageSystem
- Structure built on raft foundation
- 35m bridge 2400ton movement time lt 5 hours
- Suitable for poor subgrade conditions
- Pressure lt 10 psi
17Westlink M7 Motorway
- Standard section designed by VSL
- Works in span by span, balanced cantilever and
full span launching - Segment size 15m x 3m x 90 metric tons
- Segments can be made in advance and stockpiled
18Full Span LaunchingSegment Delivery
19Full Span LaunchingSegment Placement
20Innovative Foundations Solutions
21ABC Bridge Foundations
- Relative to superstructures, much less work in
this area - FHWA 2002 Scan Tour identified some promising
technologies - Self-Drilling Piling (grouted or screw piles)
- Continuous Flight Auger piles w/ automated
control - Cased secant piles
- Hydro-Mill continuous walls
22GRS Bridge Abutments
23GRS Bridge Abutments
24Where to From Here?
- Continue data gathering and reviews
- Determine what methods have promise
- New bridge design concepts that better use
innovative construction techniques - New / refined construction techniques for
existing / new bridge concepts - Implement new research
- Coordinate with other SHRP2 projects
- R02 Foundations
- R07 Performance Specifications
- R19 100 yr service life
25Thank You
- Dr. Francesco M. Russo, P.E.
- FRUSSO_at_HNTB.COM