Development and Design of Low Wave Reflection Seawall for Central Reclamation Phase III - Hong Kong

Abstract

This paper describes the development and design of a low refection vertical seawall for use in Phase III of the Central Reclamation (CRIII) project in Victoria Harbour, Hang Kang. Victoria Harbour is generally well sheltered from swells and provides a safe operating environment for vessels under normal conditions. In recent years, however, wave conditions in certain parts of the harbour have deteriorated. These undesirable wave conditions are caused by a combination of increased shipping activity and the construction of an increasing number of vertical blockwork seawalls which have attracted a lot of criticism these days. As a result, cargo handling, ship berthing and other port-related activities have been adversely affected. To counter this deterioration in wave conditions, the Hong Kong Government issued a directive in 1995 that all new marine structures in the Harbour Area must be designed as low wave reflection structures. A maximum wave reflection coefficient of 0.5 is stipulated. This paper discusses in detail the seawall model tests undertaken to achieve a wave reflection coefficient of 0.5. The paper also discusses how the seawall model was selected for the test. Finally, the paper discusses how the results of the tests were analysed and used for the refinement of the original concept to obtain a prototype design for a low wave reflection seawall, the finding of which is being used in the design of the Central Reclamation Phase III.