Monitoring Completed Coastal Projects: Operational Assessment of Floating Breakwaters, Puget Sound, Washington

摘要

Onsite data on the performance and durability of six floating breakwaters were gathered. Although none of the breakwaters was subjected to significant storms during the 2 years of monitoring, a number of potentially useful observations were made: These include: 1) Any large concrete float attached to shore will be used for moorage by large vessels if a demand for dock space exists. Provisions for mooring of large vessels should be an integral part of the breakwater design if there is even a remote chance that the breakwater will be used in this manner; 2) Concrete floats should be designed with rounded corners to lessen the possibility of damage from impacts; 3) Design and positioning of electrical service outlets should consider the possibility of damage by docking or departing boats, and electrical junction boxes located on the float should be equipped with drains. All hardware which supports electrical equipment should be specifically designed for marine use; and 4) Without a corrosion protection system, the service life of 1-in.-diam anchor chain is between 5 and 10 years in a temperate marine environment. After 2 years, the aluminum anodes that protect the galvanized steel anchor lines at Friday Harbor appear to be working very well. This type of anchor system may provide a service life that is significantly longer than that of an unprotected chain anchor line.