| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a ground improvement device which is used for marine work, and in which short shafts can be additionally joined in a well-balanced and efficient manner, in sequence.SOLUTION: In a ground improvement device 10, a plurality of short relay shafts 30 are additionally joined to the upper end of the short relay shaft 30 additionally joined to the upper end of a digging agitation shaft 20 on a hull 2, in sequence, until the digging agitation shaft 20 can freely penetrate into an improved ground C in a sea A down to a predetermined depth, solidifying agent is discharged from the discharge port of the digging agitation shaft 20 and filled into the improved ground C, and dug soil D and the solidifying agent are agitated and mixed to construct an improvement pile F. A joint shaft 13 is provided on a driving machine 12 for connecting the upper end of the short relay shaft 30 thereto, a shaft storage stand 40 for storing the plurality of short relay shafts 30 being erected is provided in a reciprocatingly movable manner from a standby position on the hull 2 to a connection position below the joint shaft 13 of the driving machine 12 located at a rising position, and a fixing tool is detachably provided at the connection position on the hull 2 for preventing the fall of the digging agitation shaft 20 from the hull 2.</p> |
