In the summer of 2015, discount grocer, Aldi Inc., chose a site for a new store on Gallatin Pike in Madison, Tennessee. Although only about a half mile from an existing store, the new location would replace the existing store and provide an additional 6,500 square feet of retail space.
Like all new retail commercial development, a demanding construction schedule was established to get the new store open for business. However, early in the design process, the site geotechnical investigation revealed that limestone bedrock was at very shallow depth on the site. A significant amount of slow and costly rock excavation would be necessary to transform the site to the proposed grades.
Three (3) retaining walls were needed to provide the necessary grade separation along the project site perimeter. All the walls would ultimately be situated in a rock cut very near the property line limits. With maximum design heights of 7.5 feet, the proposed retaining wall applications were a natural fit for the large, machine-placed precast concrete modular blocks of the Redi-Rock retaining wall system.
With no need for horizontal geogrid reinforcement, the selected Redi-Rock wall system relies on the mass of the dry-stacked concrete blocks to provide a gravity earth retention solution with the minimum required rock excavation.
After the walls were in place, but before site construction was complete, the City of Madison added a new challenge. The sidewalk along Gallatin Pike would need to be shifted toward the property line. This required one of the walls to be increased in height by 1.5 feet or one addition block course.
Other wall systems that require geogrid reinforcement may have needed to be deconstructed and rebuilt with longer geogrids to meet the structural requirements of the taller design height. This was not the case with the Redi-Rock solution. The modular gravity design and the structural redundancy offered by the mass of the large precast concrete units easily accommodated the additional block course without further alterations to the retaining wall already in place.
The final design included 1,914 square feet of Redi-Rock retaining wall blocks manufactured and installed by Redi-Rock K.I.T. of Mt. Washington, Kentucky. The optimized design of the Redi-Rock walls by JC Hines and Associates further limited the required rock excavation and allowed for fast, cost-effective construction that kept the project under budget and on schedule.