The early work of the Pentagon Memorial design-build team has focused on researching the fabrication and performance criteria for the 184 Memorial Units that comprise the heart of the memorial. Each Memorial Unit is a complex, yet elegantly simple, element that performs several tasks and is several things at the same time. It is an individual reflecting pool of water that glows with light at night, the place for the permanent inscription of each individual victim's name and a place to sit and place mementos. Its slender cantilevered form and the Memorial Unit's multidimensional integrity are rooted in the fabrication of its cast metal form.

The design-build team developed performance criteria for the Memorial Unit to aid in determination of the appropriate alloy to cast the benches. The criteria established the need for a metal that would last a hundred years or more, maintain structural integrity, and be compatible with other park materials and the water circulation system. Requirements for machinability, castability, and durability were also determined.

Corrosion became one of the team's most critical concerns. Based upon the original concept design, researchers began a search for an aluminum alloy that led them to contact Dr. Edgar A. Starke, Jr., Oglesby Professor of Materials Science and Engineering and Director of the Light Metals Center at University of Virginia's School of Engineering and Applied Science. Dr. Starke and colleague Robert G. Kelly, Associate Professor of Materials Science and Engineering and Co-Director of UVA's Center for Electrochemical Science and Engineering met with the team to discuss metal selection and corrosion considerations. This workshop established that aluminum could not meet the performance criteria, as corrosion was inevitable. The team began intensive research into stainless steel, titanium, and other metal options that included literature searches, extensive interviews with metals and corrosion experts and engineers, exhaustive discussions with fabricators, and visits to three representative foundries.

The research resulted in a decision by the design-build team and representative family members of the victims to produce the Memorial Units using a Super Duplex stainless steel alloy with a high pit resistance equivalent (PRE). The specific alloy is used extensively in offshore oil and gas facilities and increasingly in naval applications as it offers high strength and excellent corrosion resistance. Notably, the metal was recently used in the restoration of the Statue of Liberty, where constant exposure to salty air had corroded the monument. While more expensive than aluminum, it is significantly less expensive than titanium and offers the life cycle cost benefit of a less intensive maintenance regime. Critical to design performance, the engineered alloy meets or exceeds the metal performance criteria established for the specific application of the Pentagon Memorial - a place designed for a lifetime.

Organizations involved:

The Office of the Secretary of Defense (OSD)
Pentagon Memorial Fund, Inc.
All Family Members of Pentagon Victims
The Office of Family Policy
Washington Headquarters Services (WHS)
Defense Facilities Directorate (DFD)
The Pentagon Renovation & Construction Program Office (PENREN/C)
Design Build Team - Centex Lee, LLC
   Centex Corporation
   Lee & Associates
Kaseman Beckman Amsterdam Studio (KBAS)

At a ceremonial contract signing on August 15, 2003, the Pentagon Memorial Team officially welcomed Centex Lee LLC as the design-build team responsible for completing the Pentagon Memorial Project.

Pictured at right, the ceremonial signing of the design-build contract for the Pentagon Memorial on August 15, 2003. From left to right are John Tarpey, CEO and President of Centex Construction; Jeff Lee, President of Lee and Associates; Rosemary Dillard, Vice President of the Pentagon Memorial Fund, Inc.; Michael Sullivan, Pentagon Renovation Program Manager; Christy Skirchak (seated), Contracting Officer; Ralph Newton; Director of Defense Facilities Directorate; Julie Beckman and Keith Kaseman, Concept Designers.