PLACEMENT GRIDS, POROSITY AND RANDOMNESS OF ARMOR LAYERS

Vicente Pardo, Maria Piedad Herrera, Jorge Molines, Josep Ramon Medina

Abstract


Armor porosity and armor unit randomness are much easier to control in small-scale models constructed by hand than in prototype. Differences between design and prototype armor porosities and design and armor unit randomness can generate significant model effects. This paper describes realistic 3D placement tests with cube and Cubipod CAUs, using a small-scale crawler crane and pressure clamps. This research aims to estimate workable armor porosities at prototype scale and to determine the prototype placement grids to obtain the armor porosities commonly tested in laboratories. A new methodology based on laser scanning was developed to measure armor unit randomness. This methodology can be applied to both small-scale models and prototypes. Armor Randomness Indexes (ARIs) are proposed to measure the randomness of cube and Cubipod armor units. The ARI values were higher for Cubipods than for cubes.

Keywords


breakwater; armor unit; armor porosity; placement grid; Cubipod; random placement; randomness

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