Stanford, California

The Stanford Shopping Center Garage No. 2 was the first project designed, built, and occupied in Seismic Zone 4 to employ a precast hybrid moment frame as its lateral system. The parking garage is three levels, measures 250 feet wide by 640 feet long, and has a 1,500 car capacity. The gravity framing system consists of a conventionally-reinforced concrete slab supported by prestressed beams and prestressed columns. The parking garage was a design/build project, engineered by the San Francisco office of KPFF Consulting Engineers and built by Charles Pankow Builders, Ltd.

Because of its proximity to the San Andreas Fault, the Stanford Parking Garage was designed for near-field effects. Using the requirements of the 1997 UBC, the precast hybrid moment frame system was initially compared to a conventional concrete shear wall system. While the precast hybrid moment frame system yielded only marginal dollar cost savings, the greater advantages of the system included significantly improved damage control, increased visibility for occupants, better lighting, and faster construction.

The parking garage was constructed with the precast hybrid moment frames located primarily around the exterior edges of the garage and interior moment frames where required by diaphragm considerations. The precast columns were constructed offsite as single full-height pieces. After erecting the columns, the moment frame beams were placed. The moment frames were fully erected, grouted, and stressed prior to the construction of the rest of the structure. Construction was completed in only six months, both on time and within budget.

Contractor: Charles Pankow Builders, Ltd.