U.S. Naval Academy – Terwilliger Center Retrofit by Levelift Foundations, LLC –
When Phil Scheid of Levelift Foundations, LLC won the contract for the Terwilliger Center at the Naval Academy over fourteen other bidders, he blinked. “You always second guess yourself in a situation like this, what did I miss?” joked Scheid. For this project, the U.S. Naval Academy decided to add a second floor to the Terwilliger Center, the training center for the football team.
There were a number of troublesome site conditions that ultimately lead structural engineers Baker Ingram to specify helicals for this job. Access was limited with low overhead. Small, low-impact equipment was required as a result and the cage for the Yanmar V 35 excavator needed to be removed to squeeze into the facility. Vibration was unacceptable and there could be no compromise to the existing foundation and no spoils from the Chesapeake Bay mud used as the original fill for the site.
“Production was the key,” stated Scheid. “We knew we couldn’t move fast with all the site restrictions and the Naval Academy wanted us off-site before and during their Commission Week, with all of the accompanying ceremonies and visitors. At one point the general contractor, Manhattan Construction, raised the issue that we were getting ahead of their schedule and wanted us to slow down,” said Scheid. Fortunately, Levelift was local and mobilizations and demobilizations are not the costly impediment with helicals that they are with other piling systems.
Levelift made the most of their installation opportunities by having one crew work outside, along the perimeter of the building, while engaging 2 crews inside the facility where access restricted interior work. One hundred and ninety-eight piles were originally specified, but redesigns pushed the total to two hundred and twelve piles. 2 7/8”.203 pipe piles, grout filled to combat corrosion concerns, were installed to 70’ and 7,000 ft. lbs. of torque to achieve the 70 kip ultimate. Three helicals per pile cap were installed to support the new columns which would, in turn, support the new level.
Scheid also cited Danbro Distributor’s assistance in successfully completing the project. “Frank was considerate of our on again/off again crazy schedule and sent Nick Gill, Danbro’s site support specialist, the first week to get us off to a good start. I really appreciate Danbro’s consideration and support.”
Frank D’Angelo also cited the economic advantage that IDEAL Foundation Products, the manufacturer, brought to the equation. “We get 7,000 ft. lbs. of torque and 70 kips with IDEAL’s .203 wall. With most manufacturers you have to bump up to .276 wall to get the equivalent torque and capacity,” D’Angelo stated. “That translates into a tremendous economic advantage when you are bidding a 200 pile job. Other bidders using competitive brands can’t compete, Levelift, Danbro, and IDEAL make a great team and a tough competition for other bidders,” D’Angelo concluded.