| 摘要 |
<p>PROBLEM TO BE SOLVED: To secure a pressure tight facilitation in the sideway of tube and to prevent deformation of the tube by laying a rigid auxiliary tube more deformative than a tube burried in the ground as well as the ground, above the tube and in parallel therewith. SOLUTION: An auxiliary tube 2 is burried in the vicinity of the ground surface above a tube 1 burried in the ground. Deformation or the like in the tube 2 caused by earth pressure and the like is measured mechanically using a tube flatness measuring device or the like and thereby deformation of the tube 1 can be predicted. An equation ofΔD/D=K.ΔD0 /D0 is established, where the outer dia. of the tube 1 is D, the outer dia. of the tube 2 is D0 , deformation of the formerΔD and the latterΔD0 . The constant K is determinated according to the rigidity and material of pipe, construction conditions and burried position of footing part and the like. The deformation of the tube 1 is proportional to the outer dia. of the tube 1 and is inversely proportional to the dia. of the tube 2, and accordingly to restrain the deformation of the tube 1 the outer dia. of the tube 2 is increased.</p> |
