Special Urban Parking with Small-Town Feel

April, 2007

Adequate parking for mall shoppers often means an adjoining, multi-level parking deck. But when a retail district moves beside a residential area, a mammoth deck would overwhelm the neighbors and blow away any semblance of a dignified street line.
To ensure that the Edgewood Retail District in Atlanta, GA, would enhance — and not detract from — the neighborhood, the project incorporated some special approaches to parking, as well as various architectural details, that mimicked a residential look and feel.
Located on a 37-acre site in metro Atlanta, the 536,604-square-foot Edgewood Retail District offers eight big-box retail stores and numerous small retail shops. With limitations on both parking deck size and the ground-level area around the big brand stores, the district had only one other place to go to accumulate the necessary parking: down.
A five-acre portion of the site had a natural grade, making it ideal for a hidden parking deck. This also served a dual purpose by elevating the ground level to meet the street.
Vertically integrating big-box retail and parking provided the spaces required for a successful retail complex, but it also created some serious challenges. Chief among them was stacking big-box retail and parking across the top of a parking deck.
To achieve structural integrity, Tindall Corp. designed two new products for the Edgewood Retail District: cantilevered retaining walls and tri-slabs.
Precast retaining walls surrounding the underground parking structure act as shear walls for the structures and provide support for the beams, double tees and tri-slabs. The retaining walls are 8 inches thick and 14 feet tall and designed as cantilevered walls with precast buttresses on the side facing the retained earth, which allowed the walls to be back-filled before completion of the precast structure.
The tri-slabs and their composite construction were integral parts of attaining the stringent design requirements to support the big-box retail areas over the parking. The design used wet-connections to tie the structure together.
The structure supporting big-box retail was engineered for beam continuity under live load, and deflection limitations were kept to L/800 for reduced maintenance concerns. Live load on retail areas was 150 psf, while portions of the parking area were designed for HS-20 live loading.
Stairs and elevators allow access from the underground parking to the front of all stores, ensuring shoppers in the lowest level will have the same distance, or less, to walk as those in ground-level spaces. Sixteen-inch lite-frames were used in the multi-level parking deck to provide optimal openness in the underground parking areas – an additional safety feature for the retail shoppers.
The entire precast structure, including exterior cladding panels, was erected in four months. The speed of precast, prestressed concrete was an essential factor in completing the project on schedule. Problems with the soil and excessive rain made the precast retaining walls essential for saving the overall schedule.
Other advantages from using the all-precast structure include providing a more economical system that met structural performance requirements and reducing the number of trades involved in the construction. This further simplified coordination and maneuvering on the tight, five-acre portion of the district. Precast, prestressed pieces totaled 927, including shear walls, double tees, columns, tri-slabs and wall panels.
Providing a shopping experience of distinction and social interaction in a setting of beautiful buildings was not an easy task. It took more than hiding parking underground to accomplish this design goal.
The focal point of the Edgewood Retail District is Main Street, which runs through the site. Lined with shops, it helps re-create the look and feel of a walkable, small-town atmosphere. Limited street parking along Main Street, next to the stores, adds to the residential feel.

Joe Golden is a Sales Engineer for Tindall Corp. He can be reached at
joegolden@tindallcorp.com.