Underground opening damage from earthquakes

Abstract

A summary of worldwide qualitative data regarding the behavior of underground openings during earthquakes is presented. This information has been collected for 192 reports of underground behavior from 85 earthquakes throughout the world. The data have been assembled into a data base to determine some of the significant factors that may affect underground stability. The parameters of interest are: (1) extent of damage; (2) overburden cover; (3) predominant rock type; (4) form of support (i.e. type of internal liner or opening support); (5) geographic location; and (6) magnitude and epicentral distance of the affecting earthquake. A significant contribution to this study is the development of a correlation between peak ground acceleration at the surface, overburden depth and damage. This relationship will allow for preliminary assessment of stability of new underground structures prior to extensive dynamic analyses. Also, the vulnerability of existing underground facilities may be assessed rapidly on the basis of the qualitative data presented herein. © 1991.