USAir Arena, Largo, Maryland, USA, 1973
Architect: Shaver Partnership
Engineer: Geiger-Berger and Associates
Credits: Ballparks, Controlled Demolition Inc.
A warped circular ring of 122 m diameter with square cross section of 2.4 m x 2.4 m. To decrease bending of the ring two additional sets of stabilizing cables were introduced, running straight across the building, one set is high and outside, the other low and inside.
On Sunday, December 15, 2002 as soon after 8:00 AM as weather and security permits, Controlled Demolition, Inc. (CDI) of Phoenix, Maryland will be performing the implosion of the US Air Arena (formerly the Capitol Center) in Largo, Maryland.
Working as a subcontractor to Potts & Callahan, Inc. (PCI) of Baltimore, Maryland (the Main Demolition Contractor), CDI was contacted to review the feasibility of felling the cable-stayed roof of the arena via explosives. PCI had determined that attempting to demolish the roof via mechanical means posed extraordinary safety concerns to workers and equipment. CDI has been contracted to fell the structure to eliminate the post-tensioned stresses in the roof tendons and bring the debris down to within 50’ of adjacent grade, the level which it can be reached with PCI’s heavy equipment.
Over the past two weeks, CDI has drilled 500 holes in the reinforced concrete support columns on three levels of the arena, in the shearwalls in the two elevator and four stairwell towers (on the east and west sides of the arena structure), and the compression ring which works with the tensioned roof tendons to support the roof membrane.
Subject to a test blast scheduled for later this week, it is anticipated that approximately 400 lb. of 75% ExGel dynamite explosives will be placed in these 500 locations throughout the structure. Sunday morning, the entire implosion sequence will last approximately 18.5 seconds from the initiation of the first nonelectric explosive delay to the final settling of debris.
The Cordish Company of Baltimore, Maryland is the Developer of the site. They have contracted with Goldin & Stafford, Inc. (GSI) of Largo, Maryland to perform site work and demolition operations. GSI subcontracted the demolition of the structure to PCI, and PCI, as noted above, retained CDI to safely fell the complex structural system.