ANALYSIS ON GROUND VIBRATION INDUCED BY INTERNAL EXPLOSION IN SUBWAY STATION

Once an internal explosion happened in a subway station, strong stress wave will occur in the surrounding soil, which will spread to the surface causing strong vibration of the buildings. In this paper, a case study of typical subway station in Tianjin is carried out to analyze the responses of surrounding soil induced by an internal explosion, including the propagation of shock wave in the soil, characteristics of ground vibration and its attenuation law. For a typical subway station in China, parametric studies are carried out to investigate the influences of explosive weight and structure buried depth on ground vibration surrounding the subway station. Further, a series of formulas concerning scaled distance and structure buried depth are derived to calculate the main parameters of ground vibration at typical positions surrounding the subway station. The results of the research can be used both to estimate the vibration safety of buildings surrounding the subway station under terrorist bombing attack, and to provide theoretical basis for the determination of structure buried depth in blast-resistant design of subway stations.