In this paper, an analytical solution for linear long wave reflection by two rectangular breakwaters is explored. A closed-form expression of wave reflection coefficient is obtained which finds two well-known analytical solutions to be its special cases, including wave reflection by a rectangular breakwater given by Mei in 1989 and wave reflection by an infinite step given by Lamb in 1932. It is found that the periodicity of the reflection coefficient as a function of kh existed for a single rectangular breakwater disappears for a pair of breakwaters, and zero reflection phenomenon mostly occurs for symmetrical breakwater structure. It is also shown that the total reflection effect will be enhanced when a new breakwater is added into an existing one or when a single breakwater is decomposed into a pair of breakwaters even if the resulting total sectional area is reduced. Finally, the influence of the width of twin breakwaters to the peak Bragg reflection is studied.

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