| 摘要 |
PURPOSE:To shorten the period of construction as well as simplify operations by a method in which steel struts and precast concrete step plates are produced in factory and assembled on site into a spiral step where the step plates are spirally arranged. CONSTITUTION:A strut 3 is made of a steel pipe, and a step plate 5 is a precast concrete plate with reinforcing parts 11, in which holes 5 are formed in the fitting parts 5A of the plate 5. A slip preventer 19 is set on the side edge of the step plate 5B and the step face is unevenly formed. The plate 5 is fitted into the strut 3, during which period the plates 5 are orderly stacked up at an interval in the circumferential direction of the strut 3 and fixed with the struts 3. Since the struts 3 and the plate 5 are separately produced and assem bled on site, the needs for complicated finishing operation can be eliminated and operations on site can be simply made without use of cranes, etc., raising the efficiency of construction work. |
