| 摘要 |
PROBLEM TO BE SOLVED: To easily separate a box and concrete when disassembling a counterweight formed by filling the concrete in the metallic box.SOLUTION: This counterweight is formed by filling the concrete 2 in the metallic box 1. When disassembling the counterweight, the concrete 2 is easily torn off from an inner surface of the box 1 together with a water impermeable bag 3, by wrapping the concrete 2 with the water impermeable bag 3, and joining an outer surface of the water impermeable bag 3 in an nonadhesive state to an inner surface of the box 1. |
