配管及び支持構造物の塑性が配管系全体の地震応答に与える影響について

抄録

This paper describes the results of a series of seismic analyses conducted to clarify how plastic deformation of a pipe and its support structures affect the seismic response of the entire piping system. The first analyses include; plasticity is considered for (1)none, (2)the piping only, (3)the support structure only and (4)both the piping and the support structure. The second analyses are parametric survey of yield load and post yield stiffness of the restoring force characteristics of support structures.

The results of the first part analyses have revealed important implications on the seismic design of piping systems by elastic-plastic response analysis. First, the piping response, i.e., elbow strain typically, is significantly reduced when plasticity is taken into account in the piping support. On the contrary, it seems that the piping support response is not so much affected by the consideration of piping plasticity.

As the results of the second analyses, the yield load of the support structure has a large effect on the response of the piping system, while the post yield stiffness does not have much effect compared to the yield load.