Commercial Structure

The George Washington University Science and Engineering Hall

Ballinger AE

Washington DC

The project recognized by popular vote as this year’s overall grand project is the Science & Engineering Hall at George Washington University.  Submitted by Ballinger AE, a professional member of the CFA, this project also demonstrates the growing network of design professionals within the membership of the association.

The George Washington University- Science and Engineering Hall is a new 700,000- square-foot building located in Washington. Of the total 700,000 square-feet, 300,000-square-feet encompass the 6-story subgrade structure.

There were many unique design and construction challenges that came with such a substantial and complex subgrade structure. The substructure extends to a maximum depth of occupied space of 74-feet below grade. The perimeter basement walls were designed to withstand the intense soil pressures caused at these depths. It is also located in close proximity to three existing dormitories, which remained occupied during construction. These dormitories required deep underpinning so as not to disturb the original foundations, and also imparted a surcharge onto the new substructure walls.

Rock elevation on the site varied from 74-feet below grade to 34-feet below grade, therefore significant rock excavation was required. This was accomplished with localized blasting, which again was done while the neighboring dormitories remained occupied.
Ed Zinski, associate principal and chief structural engineer for Ballinger AE was asked about the firm’s role in the project.  “Ballinger has extensive experience with unique foundation and concrete design, as well as designing university lab spaces,” stated Zinski. “Working with our in-house design team and assisted by A&F Engineers local to Washington DC provided us with the ability to closely collaborate with the architectural and mechanical design of the building, in order to provide the most efficiently designed structure.”

Extensive computer modeling was used in all aspects of design including the deep basement walls with high soil and surcharge loads, the substructure slabs with open and sloping diaphragms translating extraordinary lateral soil loads, NIH caliber vibration resistant lab floors and high-bay post-tensioning design.

The high-bay testing lab featured a “strong-wall” and “strong-floor” designed and located 12-feet below grade level. Despite being located below grade, this lab was actually an elevated floor five stories above the building’s foundation. The elevated condition resulted in a unique design, as these types of intensely loaded labs are typically founded on grade. The design loads for the lab included more than one million pounds ultimate load applied laterally at the wall and vertically at the floor. The lab also houses a 20-ton crane and a drive-through truck receiving area to deliver specimens to the testing site. Again, extensive computer modeling was used to design this area. Ultimately it was determined that the strong-wall and strong-floor would be reinforced using solid post-tensioning rods. This is another area that required close collaboration with Clark Construction, as well as with the civil engineering faculty of George Washington University during design and construction.

Also located within the building are several sloping columns, column transfers and a central core transfer with eccentric column loads of up to 5-million pounds. The slabs were designed to transfer the lateral load induced by the sloped columns. For three of the major column transfers over the main floor auditorium, it was determined that the best solution would be to utilize an exposed composite concrete and steel truss solution. Ballinger’s structural group worked closely with Clark Construction during the building of this unique truss to ensure all of the design requirements were met.

“We are thrilled that the CFA has honored our project, the George Washington University – Science and Engineering Hall, with this award,” stated Zinski. “I have long thought that something so critical as a structure’s foundation is often overlooked or taken for granted.  That is why we joined the CFA and look forward to greater participation within the organization.  This is also why we are so honored to be recognized by the CFA with this award.”

For more information on this foundation project, contact CFA Member Edward J. Zinski, PE of Ballinger at ezinski@ballinger-ae.com or (215) 446-0684.

Project Specifications:

• Size
  • Total Lin. Ft. : 1200
  • Total Sq. Ft. : 700,000
  • Walls: 5100 cu.yds
  • Footings: 1350 cu.yds
• Steel Used
  • Walls: 190 tons
  • Footings: 52 tons
• Wall Height: Total of 74′
• Wall Thickness: Varies between 20″ and 32″