AJBP7 is a four-story, high-security tilt-up office building. IMEG’s structural engineers collaborated with other project team members to design this facility to meet progressive collapse prevention requirements without using perimeter columns, the first in the tilt-up industry to do so.

The facility is designed to meet the U.S. Department of Defense (DoD) Medium Level of Protection blast and progressive collapse resistance requirements. The structure consists of 32 load bearing tilt-up concrete panels, typically 30-ft wide and 64-ft tall. The tallest panel is 68-ft tall and weighs 125 tons. The minimum structural thickness of walls is 11 inches for blast and progressive collapse resistance, but to accommodate architectural features such as ribbon windows, the overall thickness is 15 inches.

AJBP7 is the first facility in the tilt-up industry to meet progressive collapse prevention requirements without using perimeter columns. It is beneficial to the end-users of this building to have an interior space free of perimeter columns, maximizing the available working space. Instead of perimeter columns, large connection plates are at each panel joint to provide a high level of progressive collapse resistance of the structure.

The AJBP7 structure serves as a testament to the versatility, economy, and strength of tilt-up as a building system to meet the different needs of a wide variety of building requirements. The project received a 2014 Excellence in Structural Engineering Merit Award from the Structural Engineering Association of Metropolitan Washington.