The metro system undertakes ever-increasingly important tasks to transit large passenger flows. The fire threat has become a major concern in metro stations with severe consequences because of the presence of intensive crowds. Typically, most of the metro stations are located underground with few exits and entrances. Due to the heavily crowded population and the situation of underground space, the magnitude of injuries and casualties can be overwhelmingly disastrous. Thus, a large risk comes into being where a number of evacuees may be stranded in fire accidents in metro stations. For instance, on January 12, 2015, a fire accident at the L’Enfant Plaza station platform in Washington, D.C. U.S., caused one death and 91 injuries [1]. The fire hazards and accidents have raised great public attention. The performance-based design has been commonly applied in prescriptive fire safety codes for safety consideration [2].