Underground Structures of the Seoul Sungnyemun Gate

Background/Objectives: This study was to understand non-destructively the underground characteristics on the lower structure of the Sungnyemun Gate (Korea National Treasure No. 1) using geophysical investigation methods of refraction and electrical surveys, and to make an inter-comparison between the excavation surveys. Methods/Statistical Analysis: As the result of geophysical investigation, the ground in the north of the Sungnyemun Gate (hereafter the Gate) showed a relatively fast seismic velocity GL(-) 15.0m at the point of 12.0m and 40m. Findings: Through the excavation survey, it was confirmed that the spot was the border between the main body construction of the Gate, and the core pebbles came out about 1.0 to 1.8m higher than the main body construction section. Applications/Improvement: From this, it can be concluded that by way of the distribution of refraction and excavation survey of geophysical investigation, the locations of the core pebbles at the lower part of the Gate did concur.