The installation was designed to act as both a breakwater and a dock with finger piers attached to create slips. Bob Rashleger of Skipper Marine Development explained that installing a strong floating breakwater was essential to this site “because the marina is located approximately 200 feet from a channel which accommodates frequent traffic from ocean-going freighters.”

According to Shoremaster’s engineering calculations, the breakwater is exposed to relatively short period waves of up to three feet from peak to trough. The Sturgeon Bay site is also exposed to annual ice conditions. Based on Shoremaster’s on-site engineering and Rixobryggan’s experience north of the Arctic Circle, it was determined that Rixo’s Model 450 would be an ideal combination breakwater/dock for the location.

In Raleigh, N.C., Shoremaster installed a 600-foot Rixo-bryggan breakwater surrounding the Crosswinds Marina. The Crosswinds Marina accommodates approximately 200 boats and is operated under a lease with the Corps of Engineers. A breakwater was required to protect against boat wakes and the waves resulting from two miles of open fetch in front of the marina.

While both sites are affected by adverse conditions, Shoremaster’s engineering staff is not worried. As explained by Dennis Tuel, P.E., “when you have a product that has been tested by the North Sea, you know that it will withstand these conditions.”

The strength of the Rixo-bryggan breakwater is derived from its patented connection technology. Using the Rixo connection, the concrete units are connected with cables running through hollow tubes, molded inside the concrete, hermetically sealed and completely protected against water and air. Polyurethane spacers are placed at the connection points between the floats. It is the cables and the polyurethane spacers which absorb the movement of the concrete floats as they rise and fall in the water as the result of wave action. While other connection systems inevitably transfer tension force to the concrete, the Rixo cables and spacers absorb the energy allow slight movement between the sections and remove damaging from directly affecting the concrete.

In September, Shoremaster entered into an agreement to license the patented connection technology developed by Rixo-bryggan and to begin the direct manufacture of their products.

Shoremaster has been manufacturing aluminum and galvanized steel dock systems for more than 25 years and is based in Fergus Falls.