Rao, M.Rao, S.Shirlal, K.G.2026-02-052011International Journal of Earth Sciences and Engineering, 2011, 4, 5, pp. 253-2609745904https://idr.nitk.ac.in/handle/123456789/27315The 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 (K<inf>t</inf>) of 0.38-0.708, wave dissipates energy and protect the breakwater optimally. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Coastal engineeringConcretesConvergence of numerical methodsReefsArmour unitsPhysical modelRegular wavesRelative heightsTransmission coefficientsWavebreakingBreakwaters