Case analysis of catastrophic underground pipeline gas explosion in Taiwan

•Gas leaked in populous residential area and caused a series of explosions that extended to large areas.•It is the largest petroleum catastrophe in Taiwan's history.•The cause of large area pipeline gas explosion was investigated.•The metallographic studies of rupture pipelines were conducted.

This study is related to underground pipeline gas explosions that occurred in the southern region of Taiwan in July 2014. This disaster, which resulted in substantial numbers of fatalities and injuries in addition to about 6 km of damaged roads, was the largest petroleum catastrophe in Taiwan's history.Because pipeline gas explosions of such a large extent are rare, the Kaohsiung District Prosecutors Office and Kaohsiung Fire Department launched an investigation in which an author of this paper participated. The aim of this paper is to explore the causes of the explosions, thereby contributing to the prevention of similar cases in the future.First, the causes of the large explosions are thoroughly investigated. Second, metallographic studies are conducted on the ruptured pipelines. Finally, the results are summarized, and conclusions are drawn.