The conventional method used for covering shore protection by armor stones needs not only much time for processing stones but also many divers for averaging the rubble mound, setting up and leveling stones for armoring, thereby postponing work period and leading to rise of cost.
So we have designed a new method called filter-units in place of armor stones and performed hydraulic model tests to make clear those characteristics. The filter-units consisted of small stones and wrapping nets, have abilities of reducing work period. In this paper, we firstly explain the characteristics and the construction methods of filter-units. Secondly, we detail the result of the hydraulic model test. It was found out that filter units have excellent flexibility and suitability for waves equal to that armor stones have.
