An experimental study has been performed to invetigate the basic configuration of rubble mound at the sea bed, which may be greatly influenced by a discharging
method of rubble by split hopper barge and water depth at the site.
　A hyperbolic correlation was recongnized between hopper splitting rate and stone discharge time. Introducing a stone discharge parameter of split hopper barge,φD、which is a function of such factors as stone discharge time, split width of hopper and discharged volume of stone per unit hopper length, and slso non-dimensional rubble mound shape factors, authors investigated the relationship betweem them.
　Within the present study, a linear correlation was recognized between them, but the water depth (HD) at the discharge site had a great influence on them. Then, the empirical formulae with φD and HD as parameters were proposed for expressing the basic configuration of rubble mound.
　The experimental results were compared with those of field tests and authors recongnized a good agreement between them.
　No distinguishable difference was observed in discharge of stone in waving water as long as the hopper barge was moored.