Experimental Study to Determine Forces Acting on Starbloc Armor Units and Velocities Occurring in a Single-Layer Rubble Mound Breakwater under Regular Waves

Abstract

A series of two-dimensional (2D) model tests were performed to investigate loads acting on a new artificial block (Starbloc) within a breakwater during regular waves. This block is designed as an interlocking single-layer armor block and is recommended to be placed using a regular placement pattern. Water-particle velocities in the vicinity of the armor layer were measured for several wave heights and wave periods with a laser Doppler velocimeter. A new formula is proposed concerning velocity parallel to the slope in relation to the maximum runup/rundown level. Wave force measurements were carried out on an equipped block placed below still-water level (on the armor slope). The hydrodynamic forces acting on the unit, and the corresponding force coefficients, were shown to be highly dependent on wave breaker characteristics. All the tests were undertaken with regular waves in order to fulfill a wave-by-wave analysis of the velocities and loads more easily.