This keywords page contains a comprehensive list of different types of ABC technologies, techniques, processes, and other definitions related to:

• Funding
• Incentive Programs
• Time Metrics
• Primary Drivers
• Project Planning
• Geotechnical Solutions
• Structural Solutions
• Construction Equipment / Methods

These keywords can be used for searching and should be used to aid in the new project submittal process.

ABC Project Database

Accelerated Bridge Construction (ABC)

Accelerated Bridge Construction (ABC) is bridge construction that uses innovative planning, design, materials, and construction methods in a safe and cost-effective manner to reduce the onsite construction time that occurs when building new bridges or replacing and rehabilitating existing bridges. [https://www.fhwa.dot.gov/bridge/abc/]

Time Metrics for ABC

To gauge the effectiveness of ABC, four time metrics are used:

• Overall Project Time: Overall project time is the time beginning with planning/NEPA and ending with the completion of construction.
• Project Development Time: Project development time is the time beginning with planning, including NEPA and contract plan development time, and ending on the date in which the project is advertised for construction.
• On-site Construction Time: On-site construction time is the period of time from when a contractor alters the project site location until all construction-related activity is removed. This includes, but is not limited to, the removal of maintenance of traffic items, construction materials, equipment, and personnel.
• Mobility Impact Time: Mobility impact time is any period of time the traffic flow of the transportation network is reduced due to on-site construction activities.

Mobility impact time is broken into six different impact categories. These six tiers are defined based on the length of the closure using ABC techniques.

Impact Categories:

• Tier 1:   Traffic impacts within 1 day
• Tier 2:   Traffic impacts within 3 days
• Tier 3:   Traffic impacts within 2 weeks
• Tier 4:   Traffic impacts within 1 month
• Tier 5:   Traffic impacts within 3 month
• Tier 6:   Overall project schedule is significantly reduced by months to years

Primary Drivers

PROJECT PLANNING

Decision-Making Tools 

• FHWA Process  [FHWA Decision-Making Framework] [Final Report]
• State Process
• TPF-5(221)  [AHP Decision-Making Tool];  [Final Report];  [Public Roads, November/December 2011]
• Benefit/Cost Method
• Other Decision-Making Tool

Contracting

GEOTECHNICAL SOLUTIONS

STRUCTURAL SOLUTIONS

Prefabricated Bridge Elements and Systems (PBES)

PBES are the structural components of a bridge that are built off-site or near the site of a bridge, and include features that reduce the on-site construction time and mobility impact time that would occur if conventional construction methods were used.

Prefabricated Elements

Prefabricated elements are a category of PBES which comprise a single structural component of a bridge.

Deck Elements

Deck beam elements eliminate conventional on-site deck forming activities. To reduce on-site deck forming operations, deck beam elements are typically placed in an abutting manner. Full-width beam elements eliminate conventional on-site beam placement activities. They are typically rolled, slid, or lifted into place to allow deck placement operations to begin immediately after placement. Given their size and weight, the entire deck is not included.

Pier Elements

Abutment and Wall Elements

Buried Bridge Elements

Prefabricated Systems

Prefabricated bridge systems are a category of PBES that consists of an entire superstructure, a superstructure and substructure without foundations, or a total bridge on shallow foundations, procured such that traffic operations can resume immediately or very soon after placement. Prefabricated systems are rolled, launched, slid, lifted, or otherwise transported into place as a unit, for example, having the deck and preferably the parapets in place such that any separate construction phase after placement is minimized.

Superstructure Systems

Prefabricated superstructure systems include both the deck and primary supporting members integrated such that mobility disruptions occur only as a result of the system being placed. These systems are transported into place as a unit onto existing or new abutments and/or piers.

Superstructure / Substructure Systems

Examples of prefabricated superstructure/substructure systems are rigid frames that include either the interior piers or the abutments, or buried bridge systems, without foundations. Superstructure/substructure systems are transported into place as a unit onto existing or new foundations.

• Super/Substructure System w/o Foundations
• Buried Bridge System w/o Foundations
• Other Superstructure / Substructure System

Total Bridge Systems

Prefabricated total bridge systems include the entire superstructure and substructure (both abutments and piers) on shallow foundations, made integral with the superstructure, built off-line, and transported into place as a unit onto the existing alignment.

• Super/Substructure System w/ Shallow Foundations (Rolled/Launched/Slid/Lifted)
• Other Total Bridge System

Miscellaneous

Miscellaneous Prefabricated Elements

Prefabricated miscellaneous elements either eliminate various activities that are associated with conventional bridge construction or complement the use of PBES.

Closure Joints / Connections

Definition: Pocket Connection = A connection between two prefabricated elements thru the projection of multiple bars or connectors of one element into a single void that is cast internal to the receiving element. The void is then filled with either concrete, grout, or other suitable material. (Ref.: AASHTO ABC Guide Spec)

Definition: Socket Connection = A connection between two prefabricated elements thru the projection of a single portion of one element into a single void of the receiving element. The gap between the two elements is then filled with either concrete, grout, or other suitable material. (Ref.: AASHTO ABC Guide Spec)

Overlays

ABC CONSTRUCTION EQUIPMENT  / METHODS