Session: SE-06-02 The T.H. Liu Memorial Symposium on the Seismic Analysis and Design of Piping Systems-2

Paper Number: 121747

121747 - Seismic Evaluation Method of Piping Systems by Inelastic Response Spectrum Analysis: Part 2 —Fatigue Analysis 

An inelastic response-spectrum analysis method for multi-degree-of-freedom systems was proposed. The method has lower analysis loads and good outlook given by the inelastic response-spectrum, and is not an equivalent-linearization method. We propose a seismic evaluation method of piping systems to conduct seismic design using response-spectrum analysis. The inelastic response-spectrum analysis of piping systems for the seismic evaluation method was proposed in the previous paper. The output of the analysis is the ductility factors which are defined as a ratio of maximum deformation and yield deformation of the pipe elements of the piping system: pipes, elbows, etc. The degree of inelastic of materials is shown by using the ductility factors.

In this paper, fatigue assessment of the piping system is conducted using the ductility factors. The strain range of elbows is determined from ductility factors based on finite element analyses of various geometrical and boundary conditions.The effects of difference of size or thickness of pipes are also conducted. The fatigue assessment result is compared with the vibration test result of the piping system. As a result, the degree of inelastic of materials is related to the degree of fatigue of them.

Keywords: Design, Inelastic, Piping system, Response spectrum, Fatigue assessment

Presenting Author: Satoshi Iida The Chugoku Electric Power Co., Inc.

Presenting Author Biography: Satoshi Iida is a engineer of The Chugoku Electric Power Co., Inc. His work focuses specifically on seismic evaluation of nuclear power plants.

Authors:

Satoshi Iida The Chugoku Electric Power Co., Inc.
Ichiro Tamura The Chugoku Electric Power Co., Inc.
Yorihisa Ishimaru The Chugoku Electric Power Co., Inc.
Masayuki Kamaya Institute of Nuclear Safety System, Inc.,