It is stressed in this paper that in a strong earthquake the damages of all the underground structures, chambers or any sort of underground space differed quite a lot from that on the ground surface. Numerous evidences show ground motion attenuates immensely downward with depth. However, the earthquake resistance design for underground structures still ignores this fact and sticks to the criteria of ground structures. As a result, very conservative and exhausting design for underground engineering were caused. Through a series of investigations and based on the comparison between the ground damages and the underground damages of the same site, the authors tried to establish an empirical relationship among the predicted intensity/acceleration for aseismic design, the lithology of ambient strata, depth of embedment and the geometry {width/height ratio) of the underground space/structure. As a conclusion, this paper gives a clear picture of how different the underground damages would be from the ground surface and to what range the ground movement would change due to the existence of underground space directly underneath. This approach might be useful for modifying the criteria of a design earthquake for either ground or underground construction
