Rockingham Mall Garage
Special Design Features: The developer widened a major highway for a mile and a half and built a flyover road which delivers motorists directly to the second level of the parking structure. This made the 8 acre parking structure the "front door" to the mall, and as such the owner wanted its design to be an extension of the mall environment. The challenge was how to do this in a way that was both economical and aesthetically pleasing.
Basic precast bridges are transformed into major design features at low cost with stair towers whose luminous white fabric canopies stretch over gracefully curved iron frames reminiscent of Victorian exposition halls. These elegant and dramatic fabric structures offer a counterpoint to the penanted towers of the race track nearby, as well as serving to orient both drivers and pedestrians. Lighting and signage elements on the canopies pick up mall design motifs and guide customers to the entries.
Architectural Advantages: Working closely with the manufacturer, the architect was able to incorporate decorative reveals and patterns into the spandrel columns which could be accomplished without going to architectural grade precast concrete. At a small premium, reddish aggregate was used to give color to the pieces visible from the road. Surfaces can be sandblasted in detail in the shop to vary texture.
Long Term Cost Advantage: Since long term durability and an extended warranty were important factors in selecting precast concrete, the precast subcontractor used microsilica in the double tees concrete mix, along with the highest quality caulking and expansion joints available. The microsilica significantly reduced the permeability of the concrete making it more resistant to salt penetration and deterioration.
Schedule Advantage: Time was a critical factor. because of the tightness of the site, the parking structure had to be built first to free up the site for the construction of the mall. Design-build construction of the garage structure can be done more quickly with less disruption of the site. The entire structure, including foundations was completed, under a design/build contract, within one year, and timed for the opening of the mall.
As a result of design-build efficiencies and casting mall design motifs into the structural spandrels and columns, the cost o the parking garage was lowered and the time of construction decreased. Including the cost of the steel frame stair and entry canopies, and lighting which incorporates elements of mall design, the garage was built for approximately $8,500 a space.
Structural Precast Elements:
• Precast concrete speed ramps
• Precast pedestrian bridges
• Precast stairs
• Precast Double tees