| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a staircase structure that allows people who stay under the ground to rapidly escape from under the ground to above the ground even though a large amount of water flows into a staircase. <P>SOLUTION: A staircase 1 extends from a first floor 2 to a second floor 3 that is located at a higher position than the first floor 2, and is divided into an ascending staircase part 20 and a down staircase part 30 along an ascending/descending direction. A tread 21 of the ascending staircase part 20 is located at a higher position than a tread 31 of the down staircase part 30, which is adjacent to the tread 21 of the ascending staircase part 20. A step 40 is formed between the tread 21 of the ascending staircase part 20 and the tread 31 of the down staircase part 30. A protrusion 41 that protrudes to the upper side is formed on the second floor 3 at a side close to the ascending staircase part 20. The protrusion 41 introduces water on the second floor 3 to the down staircase part 30, and the step 40 prevents water on the down staircase part 30 from flowing into an ascending staircase part 20 side. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
