Session: SE-06-01 The T.H. Liu Memorial Symposium on the Seismic Analysis and Design of Piping Systems-1

Paper Number: 123571

123571 - Effect of Friction and Gaps on Elastic-Plastic Piping Supports 

For advanced design of piping systems in nuclear power plants, various methodological studies are being conducted on designs that take into account the elastic-plasticity of piping supports. However, with regard to the elastic-plastic properties of piping supports, little research has been conducted that takes into account the friction and gaps of pipes.

Therefore, in this study, we conducted an elastic-plastic analysis of the piping support with the aim of investigating the effects of piping friction and gaps on the elastic-plastic support.

The shape under consideration is a general framework type piping support, with an aspect ratio of 1.2 or higher, where the effect of elastic-plastic behavior is expected, based on JEAC4601. The analysis model uses 3D shell elements and includes a mass element that simulates piping at the center of the supports. Friction on the pipes is considered only in the in-plane direction and is represented by a gap element with zero clearance. Horizontal gaps are represented by nonlinear springs.

The input is controlled by a triangular wave displacement, gradually increasing the displacement amplitude to perform analysis in the elastic-plastic region. The equivalent stiffness specified in JEAC4601 is calculated from the obtained load-displacement curve to determine the damping effect of the piping supports. The influence of these factors on elastic-plastic properties will be confirmed from the differences in the load displacement curve and damping effect due to the presence or absence of friction and gaps. The effect of reducing seismic response will be investigated based on the obtained damping effect.

Presenting Author: Wataru Kobayashi IHI Corporation

Presenting Author Biography: Wataru Kobayashi joined IHI Corporation in 2020 after he earned Master's degree at Tokyo University of Agriculture and Technology. Since then he works as a mechanical engineer of piping engineering department for nuclear plant construction.

Authors:

Wataru Kobayashi IHI Corporation
Akihito Otani IHI Corporation
Satoru Kai IHI Corporation