Outline1. What & How? 2. Design options3. Overview of recent projects4. Specific project details5. Performance tested in Lab6. AIT’s services “ How can we work

with you? ”

Composite Arch “Bridge-in-a-Backpack” System

What is the “ Bridge-in-a-Backpack ” System

Image Credit – NY Times/University of Maine

“ A Hybrid bridge system combining benefits of high-performance composites with durability and cost savings of cast-in-place concrete”

Carbon Fiber Composite + Concrete Arch Superstructure

Projects Completed & UnderwayStatus Bridge Location/Name

DescriptionConst.Year Key Stats

Complete(7)

Pittsfield, ME – Neal BridgePilot Project with University of Maine

2008 29.0’ Span23 Arches

Anson, ME – McGee BridgeMunicipal Design/Build Project

2009 28.0’ Span9 Arches

Bradley, ME – Jenkins BridgeMaine Composite Bridge Initiative

2010 28.5’ Span14 Arches

Auburn, ME – Jenkins BridgeMaine Composite Bridge Initiative

2010 38.0’ Span13 Arches

Belfast, ME – Perkins BridgeMaine Composite Bridge Initiative

2010 48.0’ Span16 Arches

Hermon, ME – Tom Frost Memorial BridgeSnowmobile/Pedestrian Bridge

2010 44.5’ Span3 Arches

Fitchburg, MAMA DOT Accelerated Bridge Program

2011 37.5’ Span15 Arches

Under Construction

(2)

Caribou, ME – Farm Access OverpassMaine Composite Bridge Initiative

2011 54.0’ Span22 Arches

Pinkham’s Grant, NHState Bridge Program

2011 24.5’ Span6 Arches

Design &Proposal

Bridges in design in ME, MI, proposals submitted in 11 states

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Design Options - Headwalls

• FRP Panel Walls– MSE or Through-Tied Configurations– Compatible with skewed bridges– Lightweight, easy to install– Durable, and cost competitive

• Concrete – Precast or CIP– MSE, Through-Tied, or Gravity– PC Panel, PCMG Units, Cast-in-place– Versatile design options– More conventional aesthetic

Multiple options to meet the Engineering, Economic, and Aesthetic requirements of the site

Headwall Options for Test-Level 4 Design

• Wall-mounted Barriers– Precast or CIP Gravity Wall– Precast Panel MSE Walls

McGee Bridge Replacement Example – 28’ Span

CONSTRUCTION SEQUENCE

1. Demo. existing steel bridge2. Excavate for footings3. Drill bedrock, form footings4. Arch installation5. Pour concrete footings6. Install composite decking7. Fill arches with concrete8. Erect composite headwalls9. Pour deck concrete10. Backfill bridge, install geogrid11. Finish grading12. Guardrails and cleanup

12 Days Total Construction TimeLow Bid Against Steel, Concrete, Wood

A note on footings

Perkins Bridge, Belfast, MERoyal River Bridge, Auburn, ME

Steel H-piles Spread Footings

Key Metrics• Span – 54’-2”• Rise – 12’-0½”• Rise/Span – 22%• Skew – 30 deg

• 22 – 15” Diameter Arches• Arch weight ~300lb each• Precast Concrete MSE

Headwalls/Wingwalls

Caribou Connector Bridge

Caribou Connector Bridge

Caribou Connector Bridge

How we got here- “Bridges to the future, now”

FHWA’s Public Interest Finding:• Allows for federal funding on projects where aspects deviate from typical

requirements, when in the interest of the public. i.e. in cases of “Cost-Effectiveness or System Integrity…” [FHWA]

• Simple application process – approval from FHWA in as little as 2 days

Maine’s Composites Initiative

• Six bridges in two years

• Variety of bridges to best gage how system fit’s into Maine’s bridge inventory

• 28-55’ spans• Stream/road crossing• Foundation types• Headwall designs

[FHWA Contract Administration Core Curriculum Manual, Section 3.C, http://www.fhwa.dot.gov/construction/cqit/findings.cfm]

Also being used in:

• Massachusetts

• New Hampshire

• Michigan

• Proposals in 11 states & 3 countries outside the US

Design-Build - Detail-Build - Value Engineering

Load-Deflection Response of Concrete-Filled FRP Tubular Arch

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Initial Static Test to Failure Post-Failure Behavior

Performance Testing: Arch Testing

HL-93 Design Load Equivalent

National Recognition for Bridge-in-a-Backpack

Engineering Excellence Award Royal River Bridge, Auburn, ME

(Along with Maine DOT & Kleinfelder |SEA)

AASHTO TIG - 2011 Focus Technology

Product featured in: Engineering News Record,

The NY Times,Concrete International,

Popular Science, Popular Mechanics, The Boston Globe

American Society of Civil Engineers2011 Charles Pankow Award for

Innovation

2010 Award for Composites ExcellenceMost Creative Application

Summary and Quick Facts on CFFT Arch BridgesInnovative Product Application

• Rapid fabrication our facility or option to fabricate at/near jobsite

• Hybrid composite-concrete system improves material performance

• Steel free superstructure

• Reduced carbon footprint

Performance Tested• Design/tested to exceed AASHTO load

requirements

• Superior redundancy – safe system

• Corrosion resistant materials

• Field load testing indicates even greater levels of safety

Cost Effective and Fast Installation• Light weight product– reduces equipment

transportation needs

• Erected with a small crew, no skilled labor

• Performs up to 2x lifespan of conventional materials

• Accelerated Bridge Construction

• Rapid design, fabrication, and delivery

What can AIT do for you?

• Structural Design– AIT’s engineers design the composite arch bridge superstructure– AIT can design the bridge substructure, internally or with consultants– Optimization to maximize efficiency of structure

• Supply– AIT supplies a complete engineered bridge system– Packages: arches/decking, modular FRP headwalls– Installation Oversight

Daniel BannonStructural Engineer

Jonathan KenersonManufacturing Manager