Reduction of wave impact on seashore as well as seawall by floating structure and bottom topography

  • Amandeep Kaur
  • S. C. MarthaEmail author


The three-dimensional problem involving diffraction of water wave by a finite floating rigid dock over an arbitrary bottom is studied for two cases (i) in the absence of wall (ii) in the presence of wall. The problem is handled for its solution with the aid of step method. Here both asymmetric and symmetric arbitrary bottom profile is approximated using successive steps. Step approximation helps to apply the matched eigenfunction expansion method, in result, system of algebraic equations are obtained which are solved to determine the hydrodynamic quantities, namely, force experienced by rigid floating dock as well as rigid seawall, free surface elevation, transmission & reflection coefficients associated with transmission & reflected waves respectively. The effects of various structural and system parameters are examined on these hydrodynamics quantities. The appropriate values of length and thickness of dock, water depth and angle of incidence provide the salient information to marine and coastal engineers to design the offshore structures and creation of parabolic trench on the bottom. The present results are compared with known results for special case of bottom topography. The energy balance relation is derived and checked.

Key words

Arbitrary bottom step approximation hydrodynamic quantities 


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The authors thank the reviewers and associate editor of Journal of Hydrodynamics for their comments and suggestions to improve the article in the present form. A. Kaur thanks DST, India for support through inspire fellowship.


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Copyright information

© China Ship Scientific Research Center 2019

Authors and Affiliations

  1. 1.Department of MathematicsIndian Institute of Technology RoparPunjabIndia

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