The construction accident investigation committee for the Gwangmyeong Shinansan Line collapse said on the 12th it will extend by four months, until Jan. 14 next year, the investigation period into the collapse at Section 5-2 of the Gwangmyeong Shinansan Line construction site that occurred in April. The original investigation period was until the 14th of this month.
Starting with a kickoff meeting on Apr. 17, the committee has so far held 11 committee meetings, conducted four on-site investigations, three hearings of related parties, and one meeting with related agencies. To determine the cause of the collapse, it also reviewed design documents, work logs, inspection papers, and CCTV footage.
After examining the direct causes of the collapse from multiple angles, the committee determined that a more engineering-based analysis was needed and resolved at its 11th committee meeting to extend the investigation.
During the extension, the committee will, through an external specialist firm, conduct additional borehole drilling in the accident section and geological and geotechnical investigations, perform additional structural analyses of the entire tunnel including the central column, and clearly verify various collapse scenarios.
Son Murak, committee Chairperson, said, "We are conducting a thorough, multi-faceted review by field—soil, structure, construction, and quality—to determine the cause of the accident," adding, "Through additional analysis, we will identify an objective cause of the accident and, as early as within the year, announce the investigation results and recurrence-prevention measures."