Reliability in Lifeline Earthquake Engineering

A methodology is presented that assesses the reliability of a lifeline in terms of its effectiveness to meet certain minimum performance standards after an earthquake. This effectiveness is assessed through a set of criteria that set acceptable levels of reliability and performance for the system. It is suggested that performance standards consider the health and safety of the community, as well as economic losses. They should account for different types of systems, different system and user needs, and different seismic environments. Outage potential maps are used to display the regional vulnerability of the lifeline system with respect to loss of service. These maps may be used to identify areas of weakness in the system and may be used to plan retrofitting and disaster mitigation programs.