Study on margins to fatigue damage of pipe components under cyclic loading

Abstract

It is essential to evaluate fatigue damage of piping systems, especially those in existing nuclear installations that have experienced large earthquakes. In this study, shaking table tests were conducted to understand the seismic performance of pipe components. Elbow, equal tee and reducing tee were selected as typical geometries of the components. The test results demonstrated that the location of crack penetration depends on the geometry of the components and direction of the cyclic loading. It was also confirmed that there was a large margin in the cumulative fatigue usage factor based on the current design practice, and that the piping components had a sufficient margins for fatigue damages.