Accelerated Bridge Construction: Fast, Safe, Cost Effective

Accelerated Bridge Construction (ABC) increasingly offers valuable alternatives to standard construction methods, substantially cutting down on time, costs, and safety risk related to essential roadway reconstruction.

“There are many different approaches to ABC projects, which generally involve differing construction methods as well as the types of materials used,” said GAI Sr. Engineering Manager Shaun Long, PE, MS, DBIA. “And while there have been numerous types of ABC projects performed throughout the United States, all share the common goal of completing a high-quality bridge at a far quicker pace than traditional methods.”

Pre-Built Components Come Together at Project Site

Flaugherty Run

ABC in Pennsylvania: SR 51 over Flaugherty Run, Moon Township, Allegheny County

On October 1, 2019, a bridge using the Accelerated Bridge Construction precast deck module technique reopened to traffic following an 11-day closure and detour period. GAI served as the owner’s review engineer for the design-build team’s design. GAI-provided services included preliminary and final bridge and roadway concept plans, survey, right-of-way, environmental support, public involvement, and construction phase design reviews.

“A popular ABC approach involves using precast concrete components that are formed away from the project site,” said Long, who played a key role in West Virginia’s very first Accelerated Bridge Construction project. “The precast elements are brought to the project site where they are fitted together like Lego pieces, giving the contractor the ability to proceed to subsequent phases of work without the time delay of waiting for the concrete that was used in a previous phase to cure.”

Working out of GAI’s Charleston, West Virginia location, Long is currently project manager and lead engineer on an ABC project to replace the Brick Street Bridge, part of West Virginia Route 104 in the state’s Mercer County.

Slide-In Accelerated Bridge Construction Project in West Virginia

“We’re using the ‘lateral slide’ ABC technique for the Brick Street Bridge,” said Long. In the lateral slide approach, a new bridge superstructure is constructed next to the existing bridge and a new supporting substructure is built within the existing bridge’s footprint. Traffic over the existing bridge is maintained uninterrupted while the new bridge substructure and superstructure are being built.

“The new superstructure is built on temporary supports that incorporate either mechanical rollers or Teflon sliding pads. Once all new construction is complete, we close traffic to the bridge, demolish the old structures, and ‘slide’ the new superstructure into place,” said Long. The new superstructure and substructure are then tied in and connected to the roadway.

Clear Benefits to Project Speed, Safety, and Costs

“Using this Accelerated Bridge Construction technique, the Brick Street Bridge will be out of service for 5 days while the existing bridge is demolished, the new bridge is slid over, and the tie is completed,” said Long. “Conventional construction for a project like this would usually take about 9 months.” GAI’s contributions to the Brick Street Bridge project include final design for the new bridge and the slide-in operation.

In addition to less impact on traffic, the Accelerated Bridge Construction approach offer great benefits in terms of safety and costs. “Any time you can reduce hours spent on a construction site will result in reduced safety risk for all the staff involved,” said Long. “This project acceleration also naturally results in major cost saving on construction staff man-hours as work is often reduced from months to weeks.”

Nationwide ABC Expertise

“The Accelerated Bridge Construction approach has clear advantages for high-traffic sites where lengthy traffic interruptions are problematic as well as for remote sites where necessary building materials may be difficult to source and transport to the project site,” said Long. “These are issues common to all corners of the U.S., and more and more Departments of Transportation are seeing the upside of ABC.”

“We’re fortunate at GAI to have numerous professional throughout the company that have worked on these various types of Accelerated Bridge Construction projects,” said Long. “This deep pool of experience and expertise is something that we can draw on for each and every job, working with our clients to determine the methodologies that are the best fit for each unique project.”

Contact Shaun Long, PE, MS, DBIA, 681.245.8876, for more information about Accelerated Bridge Construction and GAI’s structures and transportation engineering services.


Shaun LongShaun Long, PE, MS, DBIA is a licensed Professional Engineer in the state of West Virginia with extensive civil engineering and project management experience. Designing and managing various projects, Shaun’s areas of expertise include bridge inspection, design, analysis, plan preparation, and a thorough knowledge of transportation system evaluation, transportation planning, and traffic analysis.

Share this post: