Faculty Publications

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    Development of concrete armoured protected breakwater structure
    (CAFET INNOVA Technical Society 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2011) Rao, M.; Rao, S.; Shirlal, K.G.
    The present work involves the physical model study of stability of conventional single breakwater and the reef protected breakwater, constructed with concrete cube as an artificial armour unit. Regular waves of wide ranging heights and periods are used. The tests are carried out for different spacings between the two structures (X/d = 2.5-13.33) and for different relative heights (h/d = 0.625-0.833) and relative widths (B/d = 0.25-1.33) of the reef. It is observed that a reef of width (B/d) of 1.0-1.33 constructed at a seaward distance (X/d) of 6.25-8.33 exhibits a transmission coefficient (Kt) of 0.38-0.708, wave dissipates energy and protect the breakwater optimally. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.
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    Prediction of wave transmission over submerged reef of tandem breakwater using PSO-SVM and PSO-ANN techniques
    (Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2020) Kuntoji, G.; Rao, M.; Rao, S.
    Protection of the damaged breakwater from the high-intensity wave action has become inevitable. Submerged reef can act as a protective structure in reducing the wave action. Further, placed the reef structures on the sea side of a conventional rubble mound breakwater will reduce the effects of wave action. The conventional breakwater and reef structure combination is a tandem breakwater. Keeping in mind the end goal to decrease the complexities associated in model scaling, time constraints and cost in conducting the experiments, an attempt is made to apply soft computing techniques such as an Artificial Neural Network (ANN) and Support Vector Machine (SVM) to model various problems of real case scenario, where mathematical modelling is also difficult. In the present study, Particle Swarm Optimization (PSO) optimizes various parameters of ANN and SVM model in predicting the wave transmission over a submerged reef of the tandem breakwater. The performance of proposed hybrid models such as PSO-ANN and PSO-SVM is evaluated using statistical indices. The results show that PSO-SVM tool performs better in predicting the wave transmission compared to PSO-ANN. © 2018, © 2018 Indian Society for Hydraulics.
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    Assessment of dynamic pressure and wave forces on vertical-caisson type breakwater
    (Taylor and Francis Ltd., 2022) Kumaran, V.; Rao, M.; Rao, S.
    The design and construction of coastal structures such as breakwaters, at great water depths is rapidly increasing as a result of the increasing draught of large vessels and off-shore land reclamations. Vertical caisson breakwaters may be the best alternative compared to ordinary rubble mound breakwaters in larger water depths, in terms of performance, total costs, environmental aspects, construction time and maintenance. To fulfilling the functional utility and impact of the structure on the sea environment, it is necessary to study the hydraulic performance. This can be found by field investigation, numerical simulations and by physical modelling. Scale modelling techniques are used to study various coastal engineering problems. This article presents the results obtained by conducting series of experiments in two-dimensional wave flume to assess the hydrodynamic performance of vertical-caisson breakwater, which is made of concrete, with the protection of toe. The dynamic pressure distribution, wave runup, wave reflection, wave forces and stability parameter on the vertical caisson breakwater are discussed. The maximum wave force on the wall breakwater is calculated from measured pressure values and is compared with the forces calculated by Goda’s and Sainflou wave theories. © 2021 Informa UK Limited, trading as Taylor & Francis Group.
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    Damage Analysis of Toe for Wall Type Breakwaters
    (Springer, 2022) Kumaran, V.; Rao, M.; Rao, S.
    This study presents the result obtained from a series of experiments conducted in regular wave flume to assess the stability of toe protection for wall type breakwater. In the present paper, the determination of the size of the toe armour units and its cross-section for the stable design is presented. The applicability of the Brebner and Donnelly (Coast Eng Proc 1: 24, 1962) design curve for depth limited conditions is validated for a certain fixed relative foundation depth (d1/d) and wavelength (L), the significant wave height (Hs). The main aim of the tests is to know the stability of the toe armour units and % damage level for varying wave characteristics. The results are represented in non-dimensional graphs and it is observed that the maximum percentage damage observed for the depth of water 0.35 m is 5.2 %. © 2021, The Institution of Engineers (India).
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    Hydrodynamic performance of H-shaped floating breakwater in the presence of a partially reflecting seawall
    (Taylor and Francis Ltd., 2025) Panda, A.; Muduli, R.; Karmakar, D.; Rao, M.
    The present study examines the hydrodynamic interaction of surface gravity waves with freely floating H-shaped porous structure situated close to a partially reflecting seawall and without seawall using Multi-Domain Boundary Element Method (MDBEM). The study is performed to examine the performance of the H-shaped floating breakwater for sway, heave, and roll motion, as well as the effects of a seawall on the hydrodynamic parameters associated with the floating body. The horizontal wave force, added mass, radiation damping coefficients, and the horizontal, vertical, and moment acting on the floating structure are analysed under different structural configurations. The numerical model developed using MDBEM approach is validated using the results available in the literature. The primary findings demonstrate that reducing the structural moments and added mass and wave force coefficients, and constructing a seawall adjacent to the breakwater, greatly enhances performance in deep water. The reflection coefficient by the seawall greatly impact damping in shallow water depth but have minimal effect in deep water region, indicating that water depth significantly impacts the wave transformation. The present study provides important insights for developing marine infrastructure in various coastal and offshore environments by demonstrating the potential for customised engineering solutions to reduce wave impacts successfully. © 2025 Informa UK Limited, trading as Taylor & Francis Group.
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    Effect of seabed condition on the hydrodynamic performance of a pile-restrained H-shaped floating breakwater
    (Taylor and Francis Ltd., 2025) Panda, A.; Karmakar, D.; Rao, M.
    The present study investigates the hydrodynamic analysis of pile-restrained H-shaped porous breakwater for various seabed conditions using the small amplitude wave theory. The Multi-Domain Boundary Element Method (MDBEM) is employed to investigate the influence of parametric variations on the hydrodynamic coefficients and horizontal wave force under normal and oblique incident waves. The numerical accuracy is ensured by comparing it with the available literature. The numerical investigation on the hydrodynamic performance of the H-shaped breakwater is performed for various seabed configurations considering different angles of slope, the width of slope/step/obstacle, step height, number of steps, soil permeability, angle of wave incidence, the width of flange and submergence draft of the web of the H-shaped structure. The findings indicate that the seabed undulation has a higher wave impact on the breakwater than the horizontal seabed. In addition, the study suggests that the sloped seabed is preferable in deeper water depths to reflect waves efficiently and the seabed permeability can affect the hydrodynamic coefficients in shallow and intermediate water depths. The study performed on the H-shaped breakwater for varying seabed topography will be helpful in the design and construction of a suitable H-shaped breakwater for an effective wave absorber in coastal regions. © 2025 Informa UK Limited, trading as Taylor & Francis Group.