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Michael P. Culmo, P.E.

Vice President of Transportation and Structures

CME Associates, Inc., East Hartford, CT

Upcoming FHWA ABC Manual

Accelerated Bridge ConstructionExperience in Design, Fabrication and Erection of

Prefabricated Bridge Elements and Systems

Previously Published FHWA Manuals

2006: Decision-Making Framework for

Prefabricated Bridge Elements and

Systems

2007: Manual on the Use of Self-Propelled

Modular Transporters to Remove and

Replace Bridges

2009: Connection Details for Prefabricated Bridge

Elements and Systems

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Goal of New Manual

• Overview of all aspects of ABC

• Fill in areas that are not covered in the

other manuals

• Dovetail with “Every Day Counts” (EDC)

initiative and SHRP2

• This wide ranging program focuses on the idea of:

– Rapid renewal for highway infrastructure

• Three objectives have been identified to achieve renewal:

– Perform construction rapidly

– Cause minimal disruption

– Produce Long-Lived facilities

• Project R04: Innovative Bridge Designs for Rapid Renewal

– Project R04 documents innovative designs in more detail than this

manual

– FHWA manual will compliment this work

– Teams have been coordinating efforts

Coordination with SHRP2

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Manual Overview

Chapter 1: Introduction• Purpose of the Manual

– State of Practice in ABC

• Intended Users?

– Decision Makers

– Project Managers

– Designers

Manual Overview

Chapter 1: Introduction• Why use ABC?

– Reduces

• Overall Project Costs (in some cases)

– Reduced inspection, police and flagging

– Reduced field office rentals

– Reduced inflationary bid costs

• Cost to Society (User Costs and/or project costs)

• Environmental Impact

– Improves

• Worker safety

• Quality

• Constructability

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Manual Overview

What does ABC Cost?Rules of Thumb:

Large projects with significant repetition

ABC can be less than conventional construction

Moderate sized projects with some repetition

10% and 20% premium

Smaller projects

20% to 30% premium

Complex projects with very specialized requirements

Possibly higher

However……..

Manual Overview

ABC Costs are affected by• First time use of a design

Purchase of equipment or formwork

Cost of training for staff

Unfamiliarity of the process

Risk

• Construction time limitsIncluding fabrication timeline

• Need for specialized equipment

• Repetition of elements

• Repetition of similar projects

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Manual Overview

Chapter 1: Introduction• Public perception of ABC

– The public is our “customer”

– They prefer shorter construction

time

– Our customers fund our work

through taxes

– Legislators listen

Chapter 2: ABC Techniques:

The Manual covers all of these topics

Manual Overview

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Chapter 2: ABC Techniques: • Applicability to different bridge construction project types

– Rehabilitation

Deck replacement

Superstructure replacement

– Full Bridge Replacement

Manual Overview

Chapter 2: ABC Techniques:Foundations and

embankments

Manual Overview

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Chapter 2: ABC Techniques:Placement Methods

Manual Overview

Chapter 2:Fast Track Contracting

Design/Build

CMGC

Manual Overview

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Chapter 2:Contracting Provisions

• Best Value Selection

• A+B and A+B+C Bidding

• Incentives/Disincentives

• Warranties

Manual Overview

Manual Overview

Chapter 3:

Project Planning

and Scoping Determination of

appropriate ABC

methods

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Example Project

• Highway Overpass– Heavy traffic on overpass road (retail area)

– Relatively light traffic on interstate

– No land available nearby for large staging area

Example ProjectSuperstructure construction for bridges over roadways

or land

Consider Superstructure Pre-

fabrication combined with SPMT move

NoIs there a nearby

area for superstructure

fabrication?

Yes

Is there a clear travel path to

move the superstructure?

No

Offsite superstructure fabrication not viable

Yes

Can the travel path be cleared?

NoIs there room

adjacent to the bridge for erection of

the new superstructure?

Complete superstructure pre-fabrication not viable

Can a travel path be established on or adjacent to the

roadway?

No The use of SPMT's is not viable

Yes

Consider building superstructure on

temporary shoring towers

Consider moving the bridge in place using

lateral skidding

No

Yes

Consider moving the bridge in place using

lateral skidding or SPMT's

Yes

Consider construction in place with pre-

fabricated elements

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Example

Project

Substructure element construction

Is the project a replacement of

an existing bridge?

No

Yes

Yes

Can the new substructure be

laid out in a new footprint under

bridge?

Is there room to install new

foundation and substructure

before removal of bridge?

No

Substructure construction prior to bridge removal is

not viable

Consider construction in place prior to removal of

existing bridge

Yes

No

Consider construction in place with pre-fabricated

elements after bridge removal

Can the new bridge be built

on a new alignment?

Consider construction in place with pre-

fabricated elements

No

YesIs it feasible to use

a full width cap

beam supported on outboard

foundations?

Yes

Consider using outboard foundations with prefab.

cap installed after bridge removal

No

Can a shallow foundation be

used?(Low or no scour) Consider Geosynthetic

Reinforced Soil Integrated Bridge

System

Consider construction in place with pre-

fabricated elements

Yes

Can a shallow foundation be

used?(Low or no scour)

Consider Geosynthetic Reinforced Soil

Integrated Bridge System

Yes

No

Consider Geosynthetic Reinforced Soil Integrated

Bridge System

Can a shallow foundation be

used?(Low or no scour)

No

Yes

Consider rapid embankment

construction (geofoam)

Consider rapid embankment

construction (geofoam)

No

Manual Overview

Chapter 3:

Project Cost Analysis • Cost Evaluation

– Time and Materials Estimating

– Roadway User Costs

– Maintenance of Traffic Costs

– Safety Costs

– Agency Costs

– Life Cycle Costs

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Chapter 4:

Implementing

ABC in a

Transportation

Agency

Manual Overview

Chapter 5: Prefabricated Elements

Manual Overview

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Chapter 5:

Prefabricated

Elements

Manual Overview

Chapter 6:

Miscellaneous

Bridge Elements:Bearings

Railing/Barriers

Joints

Manual Overview

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Chapter 7: Construction• Shoring and Temporary Works

• Accelerated Submissions and

reviews

Paperless submissions

Electronic Signatures

• Fabrication

• Accelerated testing

• Erection Issues

• Field Inspection

Accelerated Decision Making

• Grouting & Closure Pours

Manual Overview

Chapter 8: Long-term

PerformanceDurability of PBES

Case Studies

Manual Overview

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Chapter 8: Long-term PerformanceCase Studies

Manual Overview

• 6 Span bridge with continuous spans

• Prestressed transversely and post tensioned longitudinally

• 42 Day construction

• Bituminous wearing surface

• Membrane Waterproofing system

• Built in 1991

• Still in excellent condition

Chapter 9: Design and AnalysisDesign of bridges for SPMT moves

Dynamic Effects

Precast Substructures

Integral Abutments

Cantilever abutment

Piers

Full Depth Deck Panels

Post tensioning

Issues not covered in LRFD

Mechanical Connectors in hinge zones

Corrugated void shear capacity

Manual Overview

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Appendices

Design Examples

Standard and Proprietary Products

Sample Special Provisions

References

Manual Overview

Manual Distribution

• Availability– Summer 2011

– Will be available through FHWA

www.fhwa.dot.gov/hfl/

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Questions

culmo@cmeengineering.com

Questions

Why are precast concrete girders not economical versus Cast in Place post

tensioned box girders in California?

This is a prime example of how multiple uses of any technology will result

in lower prices. In most states, a cast-in-place post tensioned concrete

box girder would be expensive. This is because contractors are not

familiar with the technology and they do not have the equipment

(falsework). The fact that these bridges are cost effective in California

leaves us to believe that ABC would be cost effective in any state that

employs the technology on a regular basis. Contractors have told us that

unknowns = $$. The more familiar they are with a technology, the lower

the price.

Another issue is that these bridges are not built over traffic (in general).

This reduces the cost of the construction also.

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Questions

Connection details for seismic regions?

There is significant data that has recently been published.

1. NCHRP 12-74 contains several connections between pier columns and

pier caps that have been tested.

2. The Utah DOT has details that are based on connections that are used

in buildings that are acceptable for high seismic zones in the ACI

Building Code. Caltrans is currently completing more testing on these

connections.

3. Washington DOT continues to complete significant research on seismic

connections.