| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent water from flowing out when pipes are separated by moving a pipe blocking device stored in a branch pipe of a mud delivery and mud discharge travel pipe into a mud delivery and mud discharge extension pipe by an air delivery means. SOLUTION: When mud delivery extension pipe 4 and a mud discharge extension pipe 11 are extended, a compressor 31 is driven after opening and closing a predetermined valve by a controller 33 to move a pig 23 in a branch pipe 6A into a mud feeding travel pipe 6 by air pressure. Next, the predetermined valve is opened and closed to move a pig 24 in a branch pipe 10A into a mud discharge travel pipe 10 by air pressure of the compressor 31. At this time, mud water on pipe 6, 10 sides is discharged from a water discharge pipe 15 through a predetermined pipe in accordance with the travel of pigs 23, 24. Then, the predetermined valve is opened and closed after extending pipes to return the pigs 23, 24 into the branch pipes 6A, 10A by mud water pressure. Further, the predetermined valve is opened and closed for mud water shield construction method. Consequently, since mud water and water do not flow out when the pipes are separated, it is possible to eliminate water recovery work, cleaning work, and a hindrance by water of an excavator.</p> |
