A simplified method to estimate curvatures of continuous pipelines induced by normal fault movement

Significant permanent fault rupture may occur during earthquakes and induce adverse effects on pipelines when they are located within a fault zone. Although fault movement–pipeline interaction has attracted increasing research attention recently, a simplified method that can be used to directly estimate curvatures of continuous pipelines due to normal fault movement has not been developed. In this study, a systematic finite element (FE) parametric study with 950 FE runs is conducted to investigate normal fault movement–induced bending behavior in continuous pipelines. Centrifuge test results are adopted to verify the numerical model. It is found that ground settlement due to normal fault movement is well captured by an error function. A dimensionless plot is developed between relative pipe–soil stiffness and ratio of maximum pipe curvature to maximum ground curvature. The maximum curvatures of pipelines due to normal fault movement can be estimated directly from the developed dimensionless plot. As the relative pipe–soil stiffness increases from 1.0 × 10^–4 to 1.0 × 10³, the curvature ratio decreases from 1 to 0. When the relative pipe–soil stiffness is less than 1.0 × 10^–3, the curvature ratio is close to 1. In contrast, the curvature ratio is close to zero when the relative pipe–soil stiffness is larger than 10².