Evaluation of response characteristics of buried pipelines during earthquakes

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.