A $50 million expansion project in north Nashville remains on track, as crews continue working on Interstate 65 from Trinity Lane to Dickerson Pike.
A $50 million expansion project in north Nashville remains on track, as crews continue working on Interstate 65 from Trinity Lane to Dickerson Pike. Work began in late 2012 and is set for completion later this year.
“More than 142,000 vehicles travel this section every day, making it one of the busiest corridors in metro Nashville-Davidson County,” said Heather Jensen, Tennessee Department of Transportation (TDOT) spokesperson. “The work will address safety and transition issues by adding capacity with two additional thru-lanes in each direction, and one additional lane at the I-65/I-24 merge.
“The surface of the existing roadway also needs to be replaced, so two goals are being accomplished with one project. Widening at this location is the third and final project in a larger improvement plan for I-65 that starts at Trinity Lane and ends at Vietnam Veterans Boulevard. The first two projects were completed in the late 1990s. At the time, the project was put on hold to give commuters to the north a break from construction traffic. Due to funding, the improvement plan did not resume until 2012, when the last leg of the project qualified and received a federal grant for a portion of construction costs.”
Upon completion, the roadway will contain five 12-ft. (3.7 m) lanes in each direction with a 28-ft. (8.5 m) wide median, concrete barrier and 12-ft. outside shoulders. The ramp from I-24 East to I-65 South also will be widened to provide two 12-ft. lanes. This area has a history of congestion and backup due to high traffic volumes, and these changes are designed to improve safety and capacity for all motorists traveling through the middle Tennessee area by way of I-65.
“At the present time, construction is almost complete for Phase III of the project,” said John Davis, project manager of Nashville-based prime contractor Rogers Group Inc. “Phase III included building 11 retaining walls, 16 noise walls, two box culvert extensions, road and drainage excavation and associated drainage, base stone, asphaltic base for roadway concrete and Portland cement concrete [PCC] paving for the roadway.
“Final preparations are under way, including completion of the concrete barrier wall in Phase III, associated lighting and temporary striping for the traffic switch from inside to outside lanes,” said Davis.
“Traffic will be switched to the newly constructed, outside lanes in order to begin Phase IV of the project. Phase IV involves demolition of the existing roadway, road and drainage excavation and associated drainage, bridge demolition and reconstruction and construction of the remaining PCC roadway.”
Several lanes of travel must be maintained at all times for the bulk of this project, which is a concern for crews.
“This creates a somewhat limited construction area. One of the biggest challenges of this project is maintaining three lanes of travel while building enough finished roadway to accommodate another three lanes of travel needed for the mid-project traffic shift. This project is not too different from any other road-widening project; however, maintaining traffic in the area of the I-24/I-65 merge has been challenging, due to several paving sequences and shifts needed to complete the project in both northbound and southbound directions, said Davis.”
The work involves approximately 235,000 cu. yds. (179,670 cu m) of road and drainage excavation and roughly 8,300 ft. (2,529.8 m) of pipe culvert ranging from 18 to 42 in. (45.7 to 106.7 cm) in diameter. The bridge was a two-phase construction. Phase I included demolition of approximately 13 ft. (3.9 m) of existing bridge overhang, and construction of 44 ft. (13.4 m) of new bridge. Phase II will include demolition of the existing bridge structure and reconstruction. The new bridge will be 172 ft. (52.4 m) wide and 198 ft. (60.3 m) long.
The project also calls for 200,600 tons (181,981.2 t) of base stone and approximately 224,700 sq. yds. (187,877.8 sq m) of asphaltic treated permeable base under the Portland cement concrete pavement (PCCP). Mainline PCCP is approximately 212,000 sq. yds. (177,259) and 8,514 sq. yds. (7,118. 7 sq m) in associated entrance/exit ramps.
Portland cement concrete pavement refers to the rigid concrete layer of the pavement structure directly in contact with the traffic. According to the Industrial Resources Council, typical concrete is composed of coarse aggregate (crushed stone and gravel), fine aggregate such as sand, Portland cement and water. The concrete can be modified in a number of ways. Once the concrete has been mixed, it’s placed on a prepared base coarse and consolidated and shaped, often using slip-form paving equipment. PCC pavements are subject to challenging environments and loads, so the concrete must be strong and durable.
The expansion project requires 18 noise walls, about 241,800 sq. ft. (22,463.9 sq m), and 11 retaining walls, 107,000 sq. ft. (9,940.6 sq m), in total. Two of the noise walls are off the main project, approximately two miles away on I-65, but were included in the project at the time of bid.
Hydraulic cranes were used for noise wall (installing concrete panels) and retaining wall (placing concrete) construction. Standard concrete paving equipment, as well as asphalt paving equipment, were utilized for paving operations. A concrete paving rubblizing machine also was used to remove the existing concrete roadway.
“All traffic has been shifted to the inside lanes of travel, which have been reduced to 11-foot lane widths with two-foot shoulders, inside and outside,” said Davis. “This shift and lane reduction allow for outside lane construction. Portable barrier wall is utilized to maintain a safe work zone for the motoring public and contractors. Lane closures are limited to overnight hours, between 9 p.m. and 5 a.m. Once Phase III is completed, the traffic will be shifted to the newly constructed, outside lanes to allow for Phase IV construction.
“The speed limit in the construction zone has been reduced to 45 miles per hour. Additional signage has been posted to alert the motoring public. A portable barrier wall is in place to meet safety and constructability requirements due to grade differential in areas of the project. Daily work zone inspections are also performed on site.”
Work operations are typically scheduled from 6:30 a.m. to 4:00 p.m. Monday through Friday, with some weekend work. So far, overnight work has been limited to traffic shifts, barrier wall installation and bridge beam setting.
APAC Memphis is performing the mainline concrete paving of I-65 & I-24, as well as the entrance and exit ramps.
“We began in August of 2014 and are scheduled to complete our portion of the work in October of 2015,” said Clifton Keathley, general manager.
“We’re using a Gomaco 2800 slip form paver, a Gomaco Commander III for lesser width paving lanes and a Gomaco T/C 600 tine and cure machine. All pieces of equipment are being used for the construction of the mainline paving of I-65 & I-24 and the ramps.
“We are using Irving Materials Inc. to provide Central Mix Concrete. There are approximately 80,000 cubic yards of concrete in our portion of the work.”
According to Keathley, coordination of the subcontractors’ work so they don’t interrupt each other is an ongoing issue, as is carrying out tasks in the confines of the space. Crews are working 12-hour days and, for safety, are separated from the traveling public.
Lebanon, Tenn., based LoJac Inc. is responsible for sawing, widening and sealing the contraction and construction joints in the Portland cement concrete pavement.
“I would say our biggest challenges have been scheduling and logistics,” said Donald Looney, LoJac division manager. “Our schedule is dependent upon APAC’s schedule.
“Our main equipment includes saws, trucks, trailers, along with abrasive blasting and sealing equipment,” said Looney. “Materials include saw blades, blast media and silicone sealant.”
Jensen said maintaining a safe, passable roadway and limiting the impact to drivers remains a concern as the project continues.
“The speed limit has been lowered and advance warning signs have posted to alert the public to changing traffic conditions, but three lanes of travel have been maintained in an effort to accommodate traffic volumes.”
As for the inconvenience to motorists, “TDOT strives to minimize the impact to motorists whenever possible by restricting lane closures and work schedules. Contract crews have been able to maintain three lanes of travel in each direction throughout the project. Any work that could have a significant impact on traffic flow has been accomplished overnight. Of course, the area is considered a work zone with reduced speeds and narrowed lanes. TDOT urges drivers to use caution, reduce their speed and be alert to changing traffic conditions in work zones across the state.
“TDOT makes a conscious effort to provide as much information as possible to the public,” Jensen said. “Project details are posted online. Feedback is encouraged through TDOT comments, and each comment is addressed in a timely manner. Open communication is also provided from the department to local media partners in an effort to advise the public of any project updates.”
Excessive rain last spring and summer, along with an extreme cold snap in early November, slightly pushed back the anticipated work schedule, however, the delay is not expected to affect the overall completion date of the project. Works is set for completion by October 2015.