| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide units which can be easily assembled in one body and have such strength that the units are hardly damaged when the units are transported or kept for assembling concrete boxes for underground wiring which can be adjusted in length along an underground wiring route. SOLUTION: A concrete box for underground wiring is split into, for example, left and right units 10 along a vertical plane. Therefore, when the units 10 in which side walls 12a and 13a and bottom walls 14a are united with end walls 11 are connected to each other, a concrete box can be constructed. Therefore, the concrete box can be constructed easily. In addition, since each unit 10 has a strong structure because of the end wall 11, the unit 10 is hardly broken when the unit 10 is transported, kept, or installed.</p> |
