A height gap of about 9 centimeters found on the entrance ramp at the southern end of Seoul's Seongsu Bridge has raised safety concerns among citizens. The Seoul Metropolitan Government said the gap has existed since the bridge's construction and poses no structural problem, but decided to immediately conduct a precise safety inspection and a comprehensive survey to ease public anxiety.
According to the Seoul Metropolitan Government on the 9th, the gap was identified on the ramp section connecting Olympic Boulevard heading toward Jamsil to Seongsu Bridge. It is an uphill entrance section built with soil and a retaining wall, structurally connected to the ground rather than a road suspended over the bridge.
As reports from citizens passing through the section recently continued, the Seoul Metropolitan Government conducted an on-site inspection and repaired the guardrail connection area and other parts.
The city released explanatory materials the same day, stating that "the gap was already discovered in a previous precise safety inspection and has been observed periodically." According to the city, from the 2016 precise safety inspection through this year's inspection, the size of the gap has remained unchanged at 89 to 90 millimeters (8.9 to 9 centimeters), and the on-site inspection found no progressive displacement such as additional subsidence. Progressive displacement refers to a phenomenon in which a structure continues to sink or move.
Regarding the cause of the gap, the Seoul Metropolitan Government explained that the foundation types of the Seongsu Bridge main span and the ramp retaining wall differ from each other, creating a difference in long-term subsidence. The city judged that subsidence has now stabilized, and since the central vehicle passage section of the road is paved with asphalt, there is no impact on actual vehicle operation.
"This section has been continuously managed through regular inspections in the first and second halves of each year and precise safety inspections every two years," a Seoul Metropolitan Government official said. "We judge that there is no safety concern."
However, some point out that the cause of the gap should be thoroughly re-examined, citing the past Seongsu Bridge collapse and the recent Seoso-mun overpass collapse.
In consideration of such concerns, the Seoul Metropolitan Government decided to immediately conduct outside expert consultation and a precise safety inspection, and to install measuring instruments to continuously check for changes in the facility's condition. It also plans to conduct a comprehensive survey of all connecting ramps on Han River bridges to check for similar cases and any safety abnormalities.
"This section has been closely monitored and managed for more than 10 years, and it is not a situation to worry about collapse risk or structural safety problems," a Seoul Metropolitan Government official said. "However, to ease citizens' anxiety, we will immediately conduct a safety inspection to check for any abnormalities and manage it thoroughly so that similar concerns do not recur."
