Katou, Yoshihiro

Study on Seismic Response in Substation Steel Structures

Abstract eng:
After the 2011 off the Pacific coast of Tohoku Earthquake in Japan (M9.0), it was found that the damage ratio of substation equipment was less than 1% at the substations experiencing strong ground motion with a peak ground acceleration of over 300gal. Consequently, the seismic performance of the existing substation equipment has been demonstrated. However, the steel frame structures of a substation are designed with consideration of the wind load mainly. Furthermore, there have been only few researches related to the seismic response of the steel frame. These backgrounds make difficult to establish the precise technique in seismic performance evaluation. Therefore, this paper presents the fundamental seismic response and the numerical simulation on a steel frame. The target steel frame is a two-dimensional frame structure connected to other equipment with conductors in the out-of-plane direction. To verify an analytical idealization for the seismic performance evaluation of the steel frame, a seismic observation during its operation and a dynamic numerical analysis using the finite element method were performed. In the numerical model, three models with different conditions in idealization of the conductors were generated. In one model, the conductors are not modeled. In the other two models, the conductors are modeled by point mass elements or by beam elements. We examined the effects of the conductors on the dynamic characteristics, such as natural frequency and mode shape, and the seismic response, such as the displacement of the steel frame and stresses of the structural members. Based on these results, it was found that the dynamic characteristics of the steel frame in the direction normal to the conductors were less affected by the conductors. On the other hand, the dynamic characteristics in the direction parallel to the conductors were complicated owing to the effect of the conductors. Because the stresses in the structural members during the earthquake were also affected by the conductors, a detailed model of the conductors was needed in the numerical analysis in order to obtain the reasonable evaluation.

Contributors:

Iwasaki, Shinya

Conference Title:

Proceedings of the 16th World Conference on Earthquake Engineering

Conference Title:

16th World Conference on Earthquake Engineering

Conference Venue:

Santiago (CL)

Conference Dates:

2017-01-09 / 2017-01-13

Rights:

Text je chráněný podle autorského zákona č. 121/2000 Sb.