Dorm 33 Refurbishment & Seismic Upgrade Los Angeles Air Force Base, Fort MacArthur, CA
Building 33 is a two story building over a basement level with total occupied area of approximately 14,500 sq. ft. The building has historical significance as an example of mission revival architecture. The scope of work for the renovation included the design of bathroom and kitchen plan upgrades in each dorm room performed by Parsons and the design of upgrades to the electrical, mechanical and plumbing systems throughout the building performed by Breen Engineering. The goal for the renovation work was to attain a LEED silver rating, Additionally, the building needed to be seismically retrofitted. LAAFB decided to add the re-design of the seismic retrofit to project scope of work to be performed by Breen Engineering to take advantage of the close coordination between engineering disciplines that would be necessary to achieve a cost effective viable renovation.
The seismic retrofit for the building presented several challenges. The Fort MacArthur site is situated close to the active Newport Inglewood seismic fault zone which has a high ground shaking potential. The unreinforced exterior brick walls are a significant potential hazard to building occupants. Methods to strengthen the walls were designed without affecting the historic exterior appearance of the building and were coordinated with the interior renovations to minimize disruptions to existing interiors and thereby reduce the cost of the work. Steel strong-backs and the discrete use of pneumatically applied shotcrete membranes were variously designed to strengthen brick walls avoiding costly demolition and re-construction of bathrooms and kitchen areas. Seismic ties to anchor walls at each level were also designed throughout. Previous renovations removed interior brick walls that served as shear walls further increasing the seismic risk to occupants. Floor plans were also reconfigured at each level with cross walls no longer stacked vertically. New interior shear walls were designed using innovative light gauge steel shear walls that utilize existing interior wall locations to avoid disrupting the floor plans.
The construction cost budget limit for the combined renovation and seismic upgrade work was $5.0m. Cost estimates for the work designed were $3.2m. The contract was extended to August 18, 2009 to include the seismic upgrade added to the scope of work. The final documents were delivered to LAAFB on July 15, 2009. Construction Administration was added as a separate remit to our original scope and completed in 2011.
