Author(s)

K. Fuchida

Abstract

This paper presents an evaluating method for seismic behaviour of pipelines during earthquakes and studies the response characteristics of them for various conditions of ground displacements and pipelines. The proposed method consists of mainly two analytical methods which are the seismic response analysis of surface ground layers and the pseudo static response analysis of buried pipelines. The seismic response analysis method for surface ground layers is 2-dimensional effective stress analysis based on Biot’s two phase mixture theory and Iai’s constitutive equation. The pipeline analysis is based on a beam theory on an elastic foundation and modified transfer matrix method. Numerical computations are performed for various models with changing conditions of ground and pipes. As a result, axial and lateral response characteristics of pipelines are shown and evaluated by relating with earthquakes, grounds and pipelines conditions. Keywords: response analysis, buried pipeline, surface layers, modified transfer matrix method. 1 Introduction Severe damages of lifeline systems during earthquakes much affect the social activity and urban life of citizens. It is very important that aseismic investment for lifeline systems is performed in view of fast recovery of economical and social works in urban area after earthquakes. This research aims to propose an evaluating method for seismic responses of buried pipelines and study the response characteristics of buried pipelines which are subjected to various seismic ground displacements with many conditions of pipelines and joints during earthquakes.

Keywords

response analysis, buried pipeline, surface layers, modified transfer matrix method