I-65 Widening

Benesch served as the project manager and lead design firm for the I-65 Widening Project in Robertson County. This initiative enhanced the capacity and operational efficiency of the highly traveled interstate north of Nashville by widening I-65 from near State Route 25 to near State Route 109.

The project added one additional travel lane in each direction toward the median and installed a concrete median barrier over a two-mile stretch. The scope also included modifications or replacements of multiple bridges, the incorporation of innovative construction techniques to maintain traffic flow, and the successful execution of the project on an expedited timeline.

The widening of the highway included 10 mainline bridge structures and the replacement of four overpass bridges. The 10 mainline structures, which are three span structures ranging from 120 to 180 feet in total length, were widened approximately 24 feet. Two of the four overpass structures occurred at the busy State Route 25 and 52 interchanges. TDOT strongly desired to utilize concrete girders where possible for these replacement structures. Tight grade restrictions, interstate clearances and ROW concerns were difficult challenges to overcome; however, Benesch delivered prestressed concrete box beam superstructures for three of the four overpass replacements.

Benesch was also responsible for the modeling of three mainstream crossings along the corridor. All crossings were in FEMA Zone A special flood hazard areas and required review to minimize the change in water surface elevation to less than one foot. TDOT requested that each crossing minimize the water surface elevation to the minimum extent possible. The team was able to achieve no rise in water surface elevation when comparing the existing and proposed conditions.