The Waterfront and the Plaza buildings at Quadrant Lake Union Center serve as the heart of Adobe Systems’ operations in the Pacific Northwest. The three-story U-shaped Waterfront and five-story rectangular Plaza buildings contain 296,000 square feet of office space and 200,000 square feet of parking (approximately 725 parking stalls) as part of a larger campus. To meet the needs of this prominent software development company, the buildings contain 2.2 million linear feet of data, voice, and fiber optic lines with over 10,000 ports, 9,000-amp electrical service delivered through 290 miles of wire, and 1,022 tons of mechanical cooling.
The design criteria called for high ceilings with adequate plenum space for mechanical, electrical, and communications routing. Adobe Systems, a software company that develops products and technologies for print and electronic media, requires facilities that support high mechanical (cooling) and electrical demands. At the same time, minimum floor heights were necessary to meet city-mandated building heights. Both needs were met and sight lines for neighborhood businesses and residences were preserved utilizing concrete framing.
The spans on the typical floors vary from 30- to 32-feet. A 9-inch thick post tensioned flat plate is utilized for the floor system, which was designed for an 80 pounds per square foot (PSF) live load plus a 20 PSF partition load. Isolated areas of heavy loading, including outdoor assembly and plaza spaces, were designed for a non-reducible 100 PSF live load. Shear studs are used as shear reinforcement at the 22-by-22-inch columns. This allowed as large and flexible a plenum space as possible by eliminating the need for column drop panels. It also allowed for easier mechanical and electrical access.
The lateral force resisting system consists of cast-in-place concrete shear walls, typically 12-inches thick, located around stair, restroom, and elevator cores.
In addition to the above benefits, concrete was specified on this project for the following reasons. Construction estimates during the schematic phase confirmed that concrete was the least expensive option; the fluctuating market price and availability of steel made concrete a very attractive option. Also, exposed structural components are incorporated into the architectural design. No additional fireproofing is required, since concrete provides superior fire-safety benefits, as well as sound and vibration mitigation. Finally, with an aggressive 15-month schedule, post-tensioned concrete was constructed in a shorter time frame than would have been possible with steel. Despite adverse site conditions, the foundation and the superstructure of the buildings were complete in seven months, and the entire project was finished in 13 months.
Concrete framing was the best alternative for this project, since it provided the owner a facility that met the mechanical, electrical, and space flexibility needs of a high-tech tenant. Concrete also met the tight schedule and budget, and satisfied long-term life safety needs of the occupants.
The Quadrant Corporation, Seattle, Washington
NBBJ, Seattle, Washington
Coughlin Porter Lundeen, Seattle, Washington
General/Concrete Contractor: Ready-Mix Concrete Supplier:
GLY Construction, Bellevue, Washington
Lone Star Northwest, Seattle, Washington Year: