Seoul City announced on the 26th that it will operate a three-tier inspection system focusing on key management areas to reduce the risk of subsidence incidents (ground sinking) that may occur near urban railway construction sites.
There are a total of three key management areas: the private investment project of the northeastern urban railway, the phase 4 extension of the urban subway line 9, and the complex development project of the underground space along Yeongdong-daero. These areas contain underground utilities such as water and sewage.
The three-tier inspection system consists of visual inspections, ground-penetrating radar (GPR) surveys, and smart measuring devices.
First, professional personnel and contractors will visually inspect both the surface above the underground excavation site and the interior of the construction site daily. Additionally, GPR surveys will be conducted more than once a week to check for and record any cracks or subsidence.
If empty holes are discovered underground during this process, the internal condition will be checked using an industrial endoscope camera, and immediate restoration will follow.
Furthermore, an "AI-based smart measuring device" has been installed on-site to analyze and assess risk signs and notify managers. This helps workers make quick situational judgments and safety measures, according to Seoul City.
Kim Yong-hak, head of the Seoul Urban Rail Office, said, "We will minimize safety accidents and citizen inconveniences through proactive preparation and quick responses, and strive to enhance the safety of construction sites."