Case study on earthquake impact on life lines in Hamedan province (Considering gas pipelines)

The service-rendering system in an urban community, the function of which has reciprocal effect on each other may be called the lifelines of a society that urban life depends on it enormously. In other words, the lifelines refer to those structures that urban lifedepends on them and that their malfunction results in urban malfunction, too. It seems indispensable to have sufficient knowledge regarding the vulnerability of lifelines during the earthquake and other natural disasters, as men have got close connection with theselifelines due to their daily requirements. This fact heightens the necessity of studying on the lifelines much more than before. In such studies, one may attain an appropriate method for the prediction of lifelines function during the earthquake that will exposethe managers and designers to a vast horizon and higher level of understanding.Gas pipelines are considered the most significant lifelines in an urban life. The study on the gas pipelines operation during the earthquakes occurred in the past indicates their vulnerability. They contain and carry inflammable materials, and consequently, gasleakage and fire can potentially cause danger of death by explosion, fire, and losing properties as well as causing too much environmental damages. Therefore, strengthening and upgrading the resistance of gas pipelines – particularly in earthquake zones – is of prime concern.Iran with high level of population and enjoying almost modern and valuable urban facilities encounters and faces common natural disasters, such as flood, drought, storm and noticeable environmental problems in metropolitan cities. Our country is potentially threatened with destructive earthquakes, as it is located in proximity to the active faults zone.Lifelines of metropolitans, as those in Hamedan province, are considered fundamental structures capable of wide-range servicerendering potentials to people.