PURPOSE: To discharge soil and sand in a short time without adjusting pressure by a method wherein soil and sand are mixed in a slurry circulating path, and carried outside a compressed air chamber together with slurry, and only soil and sand are separated and discarded.
CONSTITUTION: Return valves 37, 38 are opened. An outdoor slurry pressure pump 26 is operated, and the inside of a slurry return piping 16 is filled with slurry. The return valve 38 is closed, and a return valve 36 is opened. Slurry is stored in a compressed-air chamber slurry storage tank 18 up to a specified water level. A compressed-air chamber slurry pressure pump 19 is started while slurry feed valves 32, 34 are opened, thus circulating slurry. A feeder 17 is started, and excavated soil and sand are mixed nto a circulating path. Excavated soil and sand are carried simultaneously together with slurry. Excavated soil and sand are separated by a vibrating screen 30. Slurry is recirculated.
FUJIBE MASAHIRO
KATAGIRI TETSUO
MASE NOBUHIRO
