Abstract
Author experimeated the Elasto-plastic flexural behaviours of the steel truss member, and discussed the equivalent beam for the steel truss member. This paper is the fourth report of the series on the dynamic response analysis of the space structure for the earthquake. These results are as follows : (a) It is shown that the period of the equivalent beam for the steel truss member approaches to the period of the steel truss member. (b) In the experiment it is shown that the calculated deflection is smaller than the observed one. (c) It is also shown that the maximum load of the virgin compression is the largest under the alternating loads, and the deflection curves of the unloading approach to the curve of displacement for the maximum load of the virgin compression.
