"Civil Engineering Demolition Not Mandated for Pre-Design, Low-Bid Contracts Prevail"... Society Identifies Causes Behind Seosomun Overpass Collapse

Korean Society of Civil Engineers:
"Three Major Structural Gaps Led to the Accident"

Regarding the collapse accident at the Seosomun Overpass demolition site, the Korean Society of Civil Engineers has emphasized that this was "the result of structural gaps, not individual negligence," and urged for institutional reforms. The Society is regarded as the leading expert group in the civil engineering field, with more than 30,000 members including professors, researchers, and professionals from companies and organizations.

In materials released on May 28, the Society identified three major gaps in Korea’s construction regulations as the fundamental causes of this accident. First, it pointed out the lack of a mandatory requirement for pre-demolition design of civil engineering structures. While the demolition of civil engineering structures such as bridges is more complex than that of ordinary buildings, there are no regulations mandating such processes, which means that systematic demolition planning is not required during construction. The Society explained that the American Society of Civil Engineers established a dedicated technical guideline for bridge demolition in 2024 as a countermeasure.

On the 26th, at the demolition site of the Seosomun overpass in Seodaemun-gu, Seoul, the upper slab collapsed, resulting in three deaths and three injuries. Due to the risk of further collapse, recovery work has been delayed, causing disruptions in train operations including the Gyeongui-Jungang Line and KTX. The photo shows the accident site on the 27th. 2026.05.27 Photo by Dongju Yoon

There is also no system for calculating appropriate demolition project costs. The Society noted, “Costs for step-by-step structural analysis, temporary support installation, and monitoring are not properly reflected in standard cost estimates, resulting in a persistent practice of awarding contracts at low prices.” It added, “Ultimately, this leads to formalizing or chronically omitting safety procedures at demolition sites.”

According to Seoul city contracting records, the city signed a contract worth 4,072.53 million won with the contractor in April last year for the first phase of the Seosomun Overpass demolition project. At the end of the project, the contract amount was reduced by more than 600 million won due to changes in the contract terms. In February this year, an additional contract for the second phase of the project was signed for 7,889.42 million won.

The lack of standards for the expertise required in supervising the demolition of civil engineering structures was also cited as a major underlying issue. While a dedicated demolition supervision system has been established for buildings, demolition of civil engineering structures is much more difficult and complex, yet construction management is applied at the same level as for new construction projects. The Society explained, “There is currently no dedicated demolition supervision for demolition sites,” and added, “There are not even any qualification standards specialized for supervision of civil engineering structure demolition.”

On the 26th, at the Seosomun Overpass demolition site in Seodaemun-gu, Seoul, three people died and three were injured when the upper deck collapsed. Due to the risk of further collapse, recovery work has been delayed, causing disruptions to train operations such as the Gyeongui-Jungang Line and KTX. The photo shows the accident site on the 27th. 2026.05.27 Photo by Dongjoo Yoon

The Society stressed that institutional reforms are necessary to prevent additional accidents that could occur during the demolition of aging infrastructure in the future. It argued that when ordering demolition projects, it should be mandatory to conduct a preliminary demolition design, and that related standard cost estimation guidelines should be revised to provide a basis for ensuring appropriate project costs for high-risk demolition projects.

Furthermore, the Society highlighted the need to establish unified standards for demolition supervision, such as introducing qualification standards for dedicated supervisors of civil engineering structure demolition. It also pointed out the need to establish procedures that require immediate restriction of access and prioritize non-contact remote inspections upon detection of signs of collapse or other abnormalities. The Society added that a legal protection and compensation system is also necessary for private sector experts who are invited to participate in official safety inspections and suffer damages while performing their duties.

Han Seungheon, President of the Korean Society of Civil Engineers, said, “If the system fails to keep pace with developments in the field, tragedies like the Seosomun accident could occur at any time,” adding, “With thousands of similar aging bridges across the country, this accident must be the final opportunity to overhaul Korea's infrastructure safety system.”

This content was produced with the assistance of AI translation services.