CHICAGO (November 15, 2013) - The National Geospatial-Intelligence Agency (NGA) in Springfield, Va., has earned national recognition in the 2013 Innovative Design in Engineering and Architecture with Structural Steel awards program (IDEAS2). In honor of this achievement, members of the project team will be presented with awards from the American Institute of Steel Construction (AISC) during a ceremony at the project site on Nov. 19.

Conducted annually by AISC, the IDEAS2 awards recognize outstanding achievement in engineering and architecture on structural steel projects across the country. The IDEAS2 award is a prestigious honor bestowed on building projects by the structural steel industry in the U.S. and recognizes the importance of teamwork, coordination and collaboration in fostering successful construction projects.

The project team members include:

• Owner/Developer: National Geospatial-Intelligence Agency, Springfield, Va.
• Owner's Representative: U.S. Army Corps of Engineers - Baltimore District, Fort Belvoir, Va.
• Architect and Structural Engineer: RTKL/KlingStubbins joint venture, Baltimore
• General Contractor: Clark/Balfour Beatty joint venture, Bethesda, Md.
• Steel Fabricator and Detailer: SteelFab, Inc., Charlotte, N.C. (AISC Member/AISC Certified Fabricator)
• Consultant: Hinman Consulting Engineers, San Francisco

NGA is a Merit award winner in the category of projects greater than $75 Million, making it one of only eight projects around the country to receive the Merit honor. Each year, the IDEAS2 awards honor National and Merit award winners in three categories, based on constructed value. Each project is judged on its use of structural steel from both an architectural and structural engineering perspective, with an emphasis on creative solutions to the project's program requirements; applications of innovative design approaches in areas such as connections, gravity systems, lateral load resisting systems, fire protection and blast; aesthetic and visual impact of the project; innovative use of architecturally exposed structural steel; technical or architectural advances in the use of the steel; and the use of innovative design and construction methods.

Situated on the outskirts of the Capital Beltway, adjacent to the Accotink Creek, stands the NGA's 2.4 million-square-foot campus, known as New Campus East (NCE). The facility was not only designed to enhance the agency's capabilities as an intelligence organization but also to achieve a unifying, cultural transformation. This effort is expressed in the design of the nine-story main office building. Composed of two curved 900-foot-long overlapping bars around a 500-foot-long central atrium and elliptical auditorium, the building's overall form is in the shape of a lens - a fitting metaphor for NGA, a source of geospatial intelligence for the purposes of U.S. national security, defense and disaster relief.

This defining architectural expression was accomplished primarily due to the benefits of structural steel. Steel facilitated the large bay size needed for program flexibility of the typical office; reinforced the architectural concept and imagery expressed in the transparent atrium roof, west end wall and exterior V-columns; and accommodated the constraints of the highly complex technical Anti-Terrorism Force Protection (ATFP) criteria as well as a demanding schedule.

Managed by the U.S. Army Corps of Engineers - Baltimore District, the project has its origins in the 2005 Base Realignment and Closure Act (BRAC). RTKL Associates Inc. and KlingStubbins formed a joint venture to provide design services, including master planning and full architecture, engineering, interiors, site/civil, landscape and technology design.

At 2.2 million square feet, the nine-story main office building is the second largest single-occupancy building in the world (after the Pentagon) and the largest federal building in the world to achieve LEED Gold certification from the U.S. Green Building Council.

To fill the central atrium and interior of the building with light, the west end wall of the atrium was glazed with a curtain wall system, and the roof of the atrium was covered with a transparent fabric membrane. The west end atrium wall consists of a 135-foot-tall by 140-foot-wide curtain wall backed by a round HSS steel space frame. AESS requirements were incorporated into the design, fabrication and erection of the space frame structure, which served several functions. In addition to supporting the gravity loads of the curtain wall, it supports atrium roof gravity and wind loads and meets all mandated ATFP criteria. It also acts as a pedestrian bridge at several levels, providing access and circulation between the towers.

"The various bridges are an eye-catching aspect of the structure and add convenience and function to the vast space," commented Jacob Schueller, a senior in the civil engineering program at Marquette University and the student judge in the competition.

The atrium roof is more than 500 feet long, with an area of 45,000 square feet, and consists of AESS-arched HSS members supporting an air-filled ethylene tetrafluoroethylene (ETFE) fabric roof. Although it appears clear, the custom silkscreen pattern and air-filled ETFE system provide significant daylight while minimizing solar gain. Being extremely lightweight minimized ATFP-related effects and aided in reducing the tube structure size and tonnage; 18- by 12-inch built-up HSS was used for the arched roof members, which vary in span along the tapered atrium, with a maximum span of 125 feet and a 75-foot rolled radius. The roof arches span between the office towers and were designed as "springs" to accommodate independent movement of the two wings under lateral and thermal loads.

The two 900-foot wings are configured to focus on the central atrium. This dramatic space and the atrium's light-filled amenities create a "Main Street" for the office building community. Enhancing this effect are the west end atrium wall and the atrium roof structure.

The unique exterior design of the main office building was achieved as a coordinated partnership between the architect and structural engineer. Signature V-columns spaced at 40 feet on center are featured along the first- and second-floor perimeter, providing a separation between the visually solid base and the triangulated precast façade of the upper six floors, while also continuing the diagonals of the upper façade. In addition to providing a strong aesthetic statement, the V-columns participate in the lateral load-resisting system and accommodate alternate load path/progressive collapse design.

The 13 IDEAS2 winners for 2013 were chosen from nearly 100 submissions received from architectural and engineering firms throughout the U.S. Award winners are selected by a nationally recognized panel of design and construction industry professionals.

The IDEAS2 award dates back more than 70 years to the earliest years of AISC's existence. Roger E. Ferch, P.E., president of AISC, said, "The entire NGA project team has shown how structural steel can be used to create structures that combine beauty and practicality. The result is a building that serves its purpose extremely well, while providing an example of what can be achieved when designing and constructing projects with steel."