EBDG completes impact analysis for Woods Hole Terminal improvements


(SEATTLE) — Understanding the role weather can play when a vessel docks at its terminal is a subject operators face on a daily basis.  Working on behalf of the Woods Hole, Martha's Vineyard and Nantucket Steamship Authority (SSA), Elliott Bay Design Group (EBDG) was retained to determine docking impacts to their vessels' hull structure when arriving at the Woods Hole Terminal.

EBDG engineers used finite element analysis (FEA) to determine maximum pressure and stress allowed on the vessel's hull structure during a docking impact. FEA uses applied forces and constraints to calculate stress and strain on the hull during impact and provide a visual representation of the results (as shown in the image). The analysis determined allowable impact speeds with consideration of material fatigue over the vessel's life span.

The results of the impact analysis were used by SSA to assist with the design of a new fendering arrangement for its Woods Hole Terminal. Additionally, they used the data collected to determine appropriate operational procedures during inclement weather. 

"Ferry docks are like shock absorbers on a car," said Brian King, principal in charge for Elliott Bay Design Group. "You want them to be soft enough to compress and absorb the impact of a vessel but not too soft that they exceed the limits of their travel and not too hard that they damage the vessel."

This analysis gave SSA the information it needed to appropriately design the ferry dock. It will help SSA avoid costly repairs to the dock and the vessel in the future. "We also gained insight into how we can improve our vessel designs, something we are always striving to do," King said.

For more information, visit www.ebdg.com.

By Professional Mariner Staff