A Challenge Met at St. Mary’s College, MD
As part of updating their waterfront activity center, the school contracted with Dissen & Juhn Corporation to install a new bulkhead, raised piers, boat ramp, aluminum gangway, and floating boat dock. Dissen & Juhn, in turn, contracted with BoardSafe to design, construct, and deliver the aluminum gangway and floating boat dock.
The main challenge in constructing the floating boat dock was the 8-inch free board (distance between the top of the dock and water) requirement. The 8-inch free board is necessary so that the top of the racing skull is at the same elevation as the top of the dock. This allows for easy boarding and exiting of the vessel by the college’s sculling crew.
A related challenge focused on the floating dock frame. A normal floating boat dock consists of a frame that sits on top of flotation, but the St. Mary’s dock would have to be designed in such a way that the flotation was incorporated into the frame.
BoardSafe, as part of the design phase, calculated the weight of the completed frame (framing materials and decking) and determined the amount of flotation required to give the completed dock the required free board. The number of floats under the dock directly affects the free board; the greater the number of floats, the higher the free board, and the greater per square foot support. In turn, the fewer the number of floats under the dock, the lower the free board height and support per square foot. The calculations needed to substantiate the number of floats needed ultimately provided the desired free board.
The aluminum gangway was designed in accordance with current ADA specifications and measures 5-feet wide by 30-feet long. After the design was completed and approved, fabrication began at our manufacturing facility in Pennsylvania.
The custom floating boat dock frame was 10 feet by 50 feet and fabricated using our proprietary mainframe and aluminum tubing. Once the frame was completed, the specified floats were installed and the pressure-treated decking put in place as the design required.
Additional flotation was also added in the area where the gangway would rest on the floating boat dock to provide additional support for the point load created. Once completed the floating boat dock and aluminum gangway were delivered to the St. Mary’s campus and installed by Dissen & Juhn Corporation.
Both St. Mary’s and Dissen & Juhn were highly-satisfied with the custom floating dock and gangway solution BoardSafe designed and manufactured for this project.