Tunneling and underground-structure projects in Korea: General report

Korea is arguably one of the countries where the largest amounts of tunneling and underground projects are being performed. Since approximately 65% of the Korean peninsula is mountainous, tunneling cannot be avoided when constructing railroads, high-speed railroads, roads and freeways. There are also abundant urban tunneling works to construct subways, power lines, telecommunication lines, and water-supply lines, etc. Joints and fractures are well-developed in most Korean rock types. Moreover, it is common to construct tunnels through residual soils in urban tunneling. These factors make the tunneling work complicated in most cases. This paper will describe the whole picture of tunneling works in Korea and will introduce some of the challenging projects that have been encountered when designing and constructing tunnels on the Korean peninsula.