Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
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Comparative analysis of inundation flow patterns and flood risk assessment methods within subway stations

지하철 역사 내 침수 흐름 분석 및 침수 위험도 평가 방법 비교

  • Shin, Jaehyun (Department of Civil & Environmental Engineering, Gachon University) ;
  • Kim, Minjeong (Department of Civil Engineering, Seoul National University of Science and Technology) ;
  • Cho, Inhwan (Department of Civil Engineering, Seoul National University of Science and Technology) ;
  • Park, Inhwan (Department of Civil Engineering, Seoul National University of Science and Technology)
  • 신재현 (가천대학교 토목환경공학과) ;
  • 김민정 (서울과학기술대학교 건설시스템공학과) ;
  • 조인환 (서울과학기술대학교 건설시스템공학과) ;
  • 박인환 (서울과학기술대학교 건설시스템공학과)
  • Received : 2023.08.18
  • Accepted : 2023.10.10
  • Published : 2023.10.31
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Abstract

In this study, quasi-3D inundation flow simulations were conducted for a simplified subway station configuration. The effects of variations in rainwater inflow locations and discharge were investigated, analyzing the resulting inundation flow patterns and flood risk. The inundation simulation results calculated the incipient velocities for slipping and toppling accidents to assess pedestrian safety. The results indicated that velocities exceeding the incipient velocity for slipping accidents mainly occurred on the flooded staircase. Meanwhile, velocities surpassing the incipient toppling accidents were observed around the staircase and the corridor near the staircase leading to B2F. This observation is consistent with the results from the specific force distribution analysis. To provide detailed flood risk assessments, the Flood Hazard Degree (FD) was applied with four levels of criteria, along with the Flood Intensity Factor (FIF). The results demonstrated that FD identified a broader area at risk of flood-induced consequences compared to FIF. When comparing the different inundation risk assessment methods, the specific force method tended to overestimate the risk area, whereas FIF tended to underestimate it. Furthermore, among all assessment methods, the influence of rainwater discharge was found to have a more dominant effect on flood risk assessment compared to the number of rainwater inflow locations. Additionally, the direction of inundation flow influenced the assessed risk, with collision-induced flow patterns leading to higher flood risk than those with identical flow directions.

본 연구에서는 단순한 형상의 지하역사를 대상으로 준3차원 침수 흐름 시뮬레이션을 수행하였으며, 우수유입지점 수와 우수 유입량 변화에 따른 침수 흐름 특성 및 침수 위험도를 분석했다. 침수 해석 결과로부터 보행 안정성 평가를 위한 한계유속을 계산하여 미끄러짐 및 전도 사고 발생 가능 영역을 분석했다. 그 결과, 미끄러짐 사고는 침수계단에서 발생할 가능성이 있고 전도 사고는 침수계단과 지하2층 계단 주변에서 발생할 우려가 있었다. 침수 위험도에 대한 세부적 판단을 위해 4단계로 침수 위험도를 평가하는 Flood Hazard Degree (FD)와 3단계로 평가하는 Flood Intensity Factor (FIF)를 적용했다. 그 결과, FD가 FIF에 비해 더 넓은 영역에서 침수 흐름에 의한 위험이 있는 것으로 판단했다. 한계비력, 미끄러짐 및 전도 사고 발생 한계유속, FD, FIF 방법으로 평가한 침수 위험 발생 영역을 비교했을 때 한계비력은 다른 평가 방법에 비해 침수 위험 영역을 과대 산정했고, FIF는 과소산정하는 결과를 나타냈다. 또한 모든 평가 방법을 고려했을 때 우수 유입량이 우수유입지점 수보다 침수 위험도 평가 결과에 지배적 영향을 미쳤다. 또한 동일한 방향으로 침수 흐름을 일으키는 우수 유입 조건 보다 서로 충돌하는 침수 흐름을 일으키는 조건에서 침수 위험도가 증가했다.

Keywords

Acknowledgement

본 연구는 국토교통과학기술진흥원의 대심도장대터널(GTX등)의 재난대응 복합 훈련장 개발 사업연구개발과제(RS-2023-00238018)의 연구비 지원으로 수행되었습니다.

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