Kevin McAlister Presents Accelerated Bridge Construction Case Study at 2021 ABC Conference
4 / January / 2022
Kevin McAlister, PE, Barge’s Director of Bridge Engineering, presented at the 2021 ABC Conference alongside Abby Redditt, PE, Project Manager with Bell and Associates Construction, LLC. This virtual, international event focused on international projects implementing ABC methods.
McAlister and Redditt showcased the efforts of Tennessee Department of Transportation, Barge Design Solutions, and Bell and Associates to replace two aging bridges along I-24 in Hamilton County, Tennessee through the innovative Construction Manager/General Contractor (CM/GC) process using ABC techniques.
ABC, or Accelerated Bridge Construction, is a style of construction that allows for multiple tasks to occur simultaneously, rather than sequentially with no overlap. The CM/GC process is an intentionally collaborative process that allows the Construction Manager to participate in the design phase, leading to more accurate cost estimating, constructability assessments, and scheduling. This lessens change orders while minimizing risk and cost. This CM/GC project is only the third of its kind in the State of Tennessee.
Initially built in 1965, the bridges’ traffic count had more than doubled over the last 40 years, reaching more than 100,000 vehicles per day with an expected increase of 4% per year. The design team enacted ABC methods to minimize traffic disruptions along this heavily traversed construction route and completed the project on a condensed schedule. Through the team’s thorough planning efforts and utilization of the alternate delivery method, the project was completed in just 18 months. Even considering the project’s complexity, only nine days of lane closures were needed. Without ABC methods, this could have been up to 510 days of daily lane closures.
The biannual ABC Conference is hosted by Florida International University and sponsored by 30 departments of transportation and highway agencies, Tennessee Department of Transportation being one of them, the client for this case study project.