A series solution for surface motion amplification due to underground group cavities: incident SH waves

By using wave function expansion method, a series solution of surface motion amplification due to underground group cavities in half-space for incident plane SH waves was given, and effects of parameters such as the frequency of the incident waves, the angle of incident waves, the distance between the two cavities, etc. on the surface motion amplification were analyzed. The results show that the underground group cavities significantly amplify the surface motion: the surface motion for twin cavities can be 1.6 times of that for single cavity, and 3.5 times of that for no cavity. It is suggested that the effect of subways on ground motion should be considered when the subways are planned and designed.