Precast Concrete Value Engineering Accommodates Difficult Site

This article describes the use of precast concrete value engineering as it was used in the Logan International Airport Central Parking Expansion Project. This project required the building of a three-level, 2900-space parking structure on top of a deteriorated, five-level parking structure. The existing parking facility needed to remain open and functional during the construction. In addition, the flight control tower is adjacent to the existing parking structure, and the site is further restricted on four sides by busy roadways. The authors describe how the engineers and designers evaluated three systems for the airport expansion project. After determining that a precast concrete system was best for the situation, the project team implemented a value engineering effort that included special rigging and erection equipment, an exceptional foundation design, and the atypical operation of gantry-mounted erection cranes above the roof of the aged, cast-in-place concrete structure. The authors describe the use of a new precast concrete facade that srves as the lateral load resisting system. They conclude that the precast concrete system provides quality, long-term durability, the desired aesthetics in the facade treatment, constructibility within an abbreviated schedule, and economy. The article includes plans and drawings, and full-color photographs of the construction of the parking garage.