FREQUENCY-ANALYSIS OF A PARALLEL FLAT PLATE-TYPE STRUCTURE IN STILL WATER .1. A MULTISPAN BEAM

This paper is part I of a two part paper. The model used in part I is a multi-span wide beam in water contained by a rigid water trough. The multi-span beam is used to imitate a typical substructure of a parall el flat plate-type structure. There exists a narrow channel between th e lower surface of the wide beam and the upper surface of the bottom p late of the water trough. By using the small parameter expansion metho d, the added mass and damping coefficients for a typical cross-section of a plate-fluid-plate system are deduced. Moreover, by means of the added water mass and damping coefficients, the free vibration frequenc ies of the simple model of a multi-span wide beam are analyzed in the first part of the paper. In the second part of this paper, the free vi bration frequencies of a complex model of a parallel flat plate-type s tructure will be analyzed. (C) 1997 Academic Press Limited.