Blackhall Road Bridge Project: Modular Decked Beams Made with Bulb Tee Girders

January 21, 2021 1:00 pm

Donn Digamon, P.E., State Bridge Engineer, Georgia Department of Transportation; Jim Aitken, P.E., Associate Vice President, CHA Consulting, Inc.; Kevin Kahle, P.E., Senior Project Manager, CHA Consulting, Inc.; and Q&A panel members Michael P. Culmo, P.E., Chief Bridge Engineer, CHA Consulting, Inc.; Mark Dolan, Project Manager, C.W. Matthews Contracting Co., Inc.; Bill Duvall, P.E., former Georgia State Bridge Engineer, now Structural Engineering Manager with Atlas Technical Consultants, LLC; Juan Velasquez, Project Manager, C.W. Matthews Contracting Co., Inc.; and Dexter Whaley, P.E., Bridge Design Group Leader, Georgia DOT

Webinar Documents:
Blackhall Road Bridge Project: Modular Decked Beams Made with Bulb Tee Girders - pdf of presentation
Q&A Session - pdf
News - January 21, 2021 - pdf of presentation

Description: The CR 661/Blackhall Road Bridge at Rum Creek southeast of Atlanta, Georgia, was replaced in 2019 using ABC to reduce impacts to the local community. Outreach with the community during design development led the design team to the conclusion that the roadway closure for this three-span bridge replacement could be, at most, 60 days. To achieve this, the design team used Modular Decked Beams cast in laydown yards at the project site. Initially a precast double tee NEXT beam was considered, but the span length of the bridge layout resulted in a design with pre-decked prestressed concrete bulb tee girders connected with ultra-high-performance concrete deck closure joints. The result was a section that is similar to a deck bulb tee girder. The flexibility of the pre-decked section solves complexities related to profile management of deck bulb tee bridges. This presentation describes project development, design and construction details, and lessons learned.

Presentation Photos/Graphics:

1) Prefabrication staging yard

2) Erection of modular decked beams

3) Placement of UHPC in deck closure joints

4) Completed bridge