Serviceability assessment of electrical power transmission systems under probabilistically stated seismic hazards: case study for Shelby County, Tennessee

摘要

Scenario earthquakes are often used to evaluate seismic vulnerability of civil infrastructure systems. While the results of such a vulnerability assessment are useful in visualising and explaining the impact of earthquakes on public infrastructure, they are conditional in nature and do not capture the risk to infrastructure systems from the seismicity that may threaten them during a specified service period. Thus, vulnerability assessments based on scenario earthquakes are not as useful for annualising insurance costs, or for designing or retrofitting infrastructure systems. In this paper, a new method to evaluate the unconditional seismic risk to infrastructure systems is proposed and is illustrated through an application to an electrical power transmission system in a region of moderate seismicity. A comparative assessment of the vulnerability of the same system to two commonly used scenario earthquakes - the so-called Maximum Probable Earthquake and Mean Characteristic Earthquake - highlights the advantages of the proposed approach.