HYDRAULIC-PNEUMATIC FLOATING FENDER -ADDITIONAL IN-SERVICE TESTS, FIRST SERIES

Abstract

Abstract : Tests of two experimental hydraulic-pneumatic floating fenders, first in a well-protected harbor (Port Hueneme) and then in a relatively exposed harbor (San Diego), are described. Each fender consists of a 50-foot-long bulkhead fronted by two air-filled and two water-filled rubber bags. Also included is information to aid engineers in increasing the energy-absorption capacity of existing dock fender systems. After 19 months of in-service tests of the floating fender it was concluded that (1) the energy-absorption capacity of the fender is adequate for a well-protected harbor such as that at Port Hueneme; (2) a fender system serving ships under navigation conditions and in a marine environment similar to those at Port Hueneme, requires a minimum energy- absorption capacity of 16 and a maximum of 50 inch-tons per 1,000 tons of ship displacement; and (3) resistance to ship motion, including the hydrodynamic mass effect, is an important parameter which requires further investigation. It is recommended that (1) full-scale tests of berthing impact be continued, particularly at exposed harbors, to determine energy requirements for other fender designs and (2) model tests of berthing impact be initiated, particularly of the resistance to motion, for use in evaluating hydrodynamic mass. Although measurements were not made at San Diego, it is concluded that the fenders provided satisfactory service but were not loaded to capacity.