This thesis explores the challenges of predicting pipeline repair rates in earthquake conditions, showing that estimates based solely on peak ground velocity, material, and pipe size are inadequate. By examining factors of safety across various materials, diameters, and installation conditions, the study demonstrates that boundary conditions such as embedment, pipe depth, and trench properties significantly impact the static safety of pipelines and, consequently, their seismic vulnerability. Focusing on transient deformations, this research analyses cross-sectional breakage of pipes under different pressures to understand their response to environmental conditions and loads. For each pipe material, between 75,000 and 135,000 cases were calculated to evaluate factors of safety based on varying initial static conditions. Although the probability of breakage was not calculated, performance across materials and sizes was demonstrated under different pipe installation conditions. Findings suggest that pipe fragility models should incorporate these pre-existing conditions, as pipelines are never at a “zero-load” state before seismic events. Additionally, as safety factors vary widely based on site and installation specifics, relying on a single design standard does not capture all seismic risks in different locations around the world. This study underscores the need for detailed site assessments to ensure more resilient pipeline infrastructure.
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