| 摘要 |
PROBLEM TO BE SOLVED: To reduce the period of construction work by constructing ducts without installing scaffolds and removing forms. SOLUTION: A plurality of ribbed plates 22 made of steel plates provided with holes 25 are formed inside an outer cylinder 20 made of steel plates. An inner cylinder 21 made of steel plates supported by the ribbed plates 22 is formed and concrete is placed in a form consisting of the outer cylinder 20, the ribbed plates 22, and the inner cylinder 21, to construct dual ducts.
|
