Kamoi, Norriyuki (Kawasaki Heavy Industries, Ltd.) | Taniguchi, Tomokazu (Kawasaki Heavy Industries, Ltd.) | Kiso, Takashi (Kawasaki Heavy Industries, Ltd.) | Kada, Kazuo (Kawasaki Heavy Industries, Ltd.) | Motoi, Tatsuya (Kawasaki Heavy Industries, Ltd.) | Nakamura, Shinichi (Kawasaki Heavy Industries, Ltd.)
The treated soil plant barge, Hakuren-go, and treated soil placing barge, Hakusei-go, have entered into service to construct a slope embankment (length 800m, breadth 83m, water depth 31 to 3m) on the sea bottom around the Kisarazu artificial island of Trans-Tokyo Bay Highway. The embankment will be formed with 993000m treated soil. The soil mixture prepared on the plant barge is pumped out by ten concreat pump units onto the placing barge. 6000m/day of the soil mixture is placed on the sea bottom using two sets of ten guide and tremie pipings alternately under the monitoring and controlling in the integrated operation room on the placing barge.
Trans-Tokyo Bay Highway shall have a connection between Kawasaki city, Kanagawa Prefecture and Kisarazu City, Chiba Prefecture passing through the center of Tokyo Bay, by under sea bottom tunnel (length 9.5km) and bridge (length 4.4km). The bridge connects to the under sea bottom tunnel through sloped embankment of artificial island. (Fig. 1) The treated oil paInt barge Hakuren-go and the treated soil placing barge Hakusei-go are newly planed and fabricated to be used for construction of the sloped embankment in February 1992.
OUTLINE OF THE TREATED SOIL EMBANKMENT
The sloped embankment shall be mounted on the sea floor With the treated soil which consists of pit sand, mud-stone slurry. cement and seawater. (Fig. 2) After construction. the embankment shall be bored by sealed boring machine for tunnel. Mixture proportion and strength of the treated soil shall be decided by the following performance; To hold the shape of the embankment. Easy execution of tunnel boring works. Therefore. the treated soil is required to keep constant mixing proportion during mixing and placing. The construction period was allowed two years only for placing. Both barges were planed and built newly for completion of the embankment under the above service condition.