Project Spotlight: Broadway Bridge Replacement
SSR recently wrapped up a CEI (Construction Engineering and Inspection) project for a replacement bridge in downtown Nashville, TN. The Broadway Bridge replacement project (also referred to as State Route 1 (US 70) Broadway Viaduct) was a TDOT Accelerated Bridge Construction (ABC) project and consisted of the replacement of a deteriorating bridge over five CSX rail tracks and 11th Avenue. To accommodate the construction, a section of Broadway was closed for eight weeks to expediate construction.
Broadway is a major throughfare in downtown Nashville and this section of road is heavily used as a route for traffic entering and exiting the city by both vehicles and pedestrians. The site is also near hotels, attractions, offices, and historic sites. The replacement bridge was designed to have the same footprint of the original bridge with three dedicated travel lanes in each direction and a median. The new bridge’s median was reduced to allow for larger sidewalks with planters on both sides of the roadway installed to separating vehicular and pedestrian traffic.
Construction Over an Active Railroad
The Broadway Bridge spans five CSX rail lines that were required to remain active throughout the project’s duration. To accommodate construction, CSX provided a signaler that would notify the construction team 30 minutes ahead of an approaching train. The crews would have to stop working, clear tracks removing cranes, and get adjacent equipment out of the way. The area was required to remain clear for 30 minutes after the train passed.
The demolition and construction also presented unique challenges as the area below needed to remain clear of debris. Demolition was performed in phases with the removal of the top asphalt layer and then chunks of the original concrete deck removed in large sections. The new bridge was comprised of prefabricated panels set on beams with concrete poured between the panels (closure pours) to join and seal. This is a standard approach for TDOT’s ABC projects but unusual for traditional bridges.
The expedited timeline required more crews on site and more frequent materials testing. SSR was onsite full time, 24/7, during the eight weeks of construction.
The Broadway Bridge officially opened two weeks ahead of schedule. The official ribbon cutting took place on Wednesday, October 18.