| 摘要 |
<p>PROBLEM TO BE SOLVED: To maximally restrain an increase in boring thrust in element propulsion time, and to surely maintain water cutoff performance by surely filling a grout material.SOLUTION: A joint structure is composed of a recessed joint 3 having a groove part 5 provided in an adjacent one steel shell element 2 and opening along the axial direction of the steel shell element 2 and a water cutoff part 6 for blocking up an opening of the groove part 5 and a projection joint 4 provided in the other steel shell element 2 and having a projection strip part 12 inserted into the opening of the groove part 5, and the water cutoff part 6 is composed of double packing 10 composed of plate spring-like packing 8 and auxiliary packing 9 of respectively extending toward the opening central direction from both sides of the opening and a water cutoff skid 11 filled between these, and the mutual auxiliary packings 9 and 9 are provided so as to have an overlapping margin in an opening central part. When fitting the mutual joints, the projection strip part 12 is fitted-inserted between both-side packings 8,etc., 9, etc. while deforming the packing 8 and the auxiliary packing 9 so as to be respectively expansively opened.</p> |
