Jackson Avenue Ramps: A Multi-Disciplinary Approach for Historical Renovation Projects
UPDATE: 2021 ACEC Tennessee's Engineering Excellence Grand Award Winner for Large (over $2.5M) Special Projects
The Jackson Avenue Ramps award-winning project applied a multi-disciplinary approach to a centennial replacement project for two structurally deficient bridges in the heart of Knoxville. The project not only retained the ramps’ architectural heritage and historic fabric, it also provided multi-modal access and connectivity to the traveling public, be they local residents, employees or customers of area businesses. The new 21st century ramps seamlessly link the elevated Gay Street to Jackson Avenue below, with close proximity to City-owned parking. This project showcases innovative engineering at the nexus of sustainable infrastructure investment, historic preservation and economic development.
Case History Jackson Avenue Ramps Project
Back in early 2008, Vaughn & Melton was contracted by the City of Knoxville to participate in the development of the engineering and architectural plans as well as the oversight and construction inspection of the renovation and restoration of the Jackson Avenue ramps in downtown Knoxville. The Jackson Avenue ramps were built in 1920 as a structural component of the original Gay Street Viaduct that spanned the Southern Railway rail yard. The only major repair work on the century-old ramps since their construction occurred between 2008 and 2010 when the east ramp was closed by Tennessee Department of Transportation (TDOT) after a routine inspection revealed some serious structural issues. The project extends only 656 feet, but the entire area, including the adjacent historic buildings, is listed in the National Register of Historic Places, (NRHP) thus adding to the complexity of the project.
There were several factors contributing to the complexity of this project. The coordination of infrastructure construction, utilities and the historical aesthetics as well as having to work within the one half-inch space between the ramps and the adjacent buildings to remove two large ramps without inflicting any damage all while maintaining a safe thoroughfare for pedestrians were the overarching challenges to the project.
In order to bring the structure back to its former glory and without any unnecessary damage, there were a number of diverse team members brought together to study and assess all the historical, socio-economical, archeological and architectural issues that could affect the project. These agencies spent an innumerable amount of hours conducting their studies and making their recommendations to the City as well as the Vaughn & Melton design team. All of these recommendations were considered and implemented in the design, modeling and construction renovation process to ensure that the historical aspects as well as the structural and architectural integrity were maintained. In addition, because of the proximity to several historic buildings -- which are also listed in the NRHP -- the owners of those buildings all had to be consulted with to ensure that the new construction would not hinder or damage the buildings and that the historical nature of the area would be preserved.
In its early days, the area in which the ramps are located was home to several railroad hotels and boarding houses that were located at the railroad yard. The surrounding area featured businesses such as restaurants and saloons patronized by railroad workers and visitors. Now, the area has evolved into a robust, energetic, and trendy commercial district with artist’s galleries, antique stores, pubs, dance clubs, and newsstands. Located in what locals call the “Old City,” the area also features private offices as well as loft apartments and condominiums.
Much like many historical places, Knoxville’s antiquities hold great value with the local community which is why so much time and effort has gone into the preservation of this unique and iconic area of downtown Knoxville.
Vaughn & Melton's recommendations included demolishing the existing elevated Jackson Avenue ramps on either side of the Gay Street Overpass, reconstruction of the ramp support structures, relocation and realignment of above ground and underground utilities, and replacement of ground-level features under the ramp. This new area under the ramps will feature a mix of retail and business space.
A significant amount of research and planning went into choosing materials that would be similar in size, scale, massing and width of the original ramps. Every feature from the brick pavers covering the ramps, support columns, the railings, and ornamental lighting fixtures all had to contain elements complimentary to original ramps. The contractor selected to replicate and fabricate the one-foot thick pavers covering the ramps was able to preserve some of the original pavers and many of those were placed alongside the new replicated pavers.
Altogether there were over 4900 man hours invested in the project in just the construction and engineering phase alone. Along with Vaughn and Melton, there were a total of 50 individuals from five other agencies who contributed their time and expertise. The nearly $10 million project spanned almost a decade and is just in the final completion stage as of February 2021.