Recently, tunnel constructions have been increased in Korea. According to the increment of tunnel constructions, cases of tunnel collapses also have been increased under tunnel construction . Among these tunnel collapses, after a certain amount of time has elapsed due to excessive displacements on slope of tunnel exit or entrance, cases of tunnel collapse have been increased rapidly. Therefore, the case study was conducted in this study to figure out factors effect on the tunnel collapses due to excessive displacements on tunnel exit or entrance slopes. Base on the case study, the fragmental zone of fault and the rainfall were most important factors on the collapse.

• 김낙영(한국도로공사 도로교통연구원, 공학박사) | Kim, Nag Young