抄録
The entitled case of structures refers to one of the cases discussed in the preceding report in which results of the analysis of three types of staircases were compared with the corresponding experimental results, as a part of studies on the method of the structural design of the reinforced concrete staircase composed of either a set of slabs or a helicoidal shell. With regard to free-standing staircases it was then confirmed that the ratio of the elastic limit to the ultimate strength of the structures decreases with the increased angle between the horizontal projections of the inner edges of their pair of flights. In case of having this angle null while varying horiontal distande between both flights of a staircase, that then lie parallel in plan, elastic and vibration analysis of the structure are presently made using the finite element method so as to clarify major characteristics of its statical and dynamical behaviors. Then these results results are used in proposing some approximate design formula that may generally be available for this type of staircase.
