ABSTRACT
Sand containers have been commonly used for wave protection and beach stabilization at coastal areas mainly due to their low construction cost and simplicity in design. In Malaysia, the majority of the breakwaters consisting of several arrrays of sand containers are installed at muddy coasts so as to provide required level of hydrodynamic regimes in its vicinity. Due to unavailability of the established design guidelines of the sand container breakwaters, the geometry of these low crested structures is largely ascertained by engineering judgement and experience of coastal engineers. The present study aims at investigating wave transmission characteristics of the submerged sand container breakwaters of different layers, i.e. single-, double-, triple- and quadruple-layers, with respect to varying water depths, breakwater submergence and wave steepness via physical modelling. The test models were subjected to unidirectional monochromatic waves of different periods and heights using a wave flume facility. Wave transmission characteristics of the respective test models were quantified in terms of wave transmission coefficients. The experimental results revealed that wave transsmission ability of the test models were largely governed by the degree of breakwater submergence and the wave steepness imposed to structures. Wave attenuation ability of sand container breakwater could be further enhanced by increasing the breakwater size and reducing the breakwater submergence.
