Abstract
A newtype of breakwater-the double cell caisson-has been developed by Ministry of Transport. The double cell breakwater has double cylindrical vertical wall, a permeable outer wall and an impermeable inner wall are fixed on a base caisson. This type of breakwater is supposed to save the total amount of the materials, so it can be economical to construct the port under severe conditions of deep sea and high wave. Before putting the new breakwater type into practical use, double cell breakwaters were constructed on a trial basis and tested in Sakai Port to see whether it would function as designed. The contents of the test are reported in this paper.
