Geosynthetic Reinforced Segmental Retaining Wall Failure Buying Heavy Rainfall - A Case Study

집중강우시 발생한 블록식 보강토 옹벽의 붕괴사례

  • 유충식 (성균관대학교 토목환경공학과) ;
  • 전한용 (인하대학교 나노시스템공학과) ;
  • 정혜영 (성균관대학교 토목환경공학과) ;
  • 정혁상 ((주)대정컨설턴트)
  • Published : 2005.06.01

Abstract

This paper presents a case history of a geosynthetics-reinforced segmental retaining wall, which collapsed during a severe rainfall immediately after the completion of the wall construction. In an attempt to identify possible causes for the collapse, a comprehensive investigation was carried out including physical and strength tests on the backfill, stability analyses on the as-built design based on the current design approaches, and slope stability analyses with pore pressure consideration. The investigation revealed that the inappropriate as-built design and the bad-quality backfill were mainly responsible for the collapse. This paper describes the site condition including wall design, details of the results of investigation and finally, lessons learned. Practical significance of the findings from this study is also discussed.

본 논문에서는 시공 직후 집중호우 기간동안 발생한 보강토 옹벽의 붕괴사례를 다루었다. 붕괴 원인을 파악하기 위해 현장답사를 실시하여 옹벽의 제원 및 각종 시료를 채취하였으며 뒤채움흙에 대한 공학적 평가, 설계기준에 근거한 안정성 검토를 수행하였다. 또한, 지속적으로 내린 강우와 옹벽의 붕괴 연관성을 검토하기 위해 불포화토 개념의 침투해석을 수행하고 이를 토대로 사면안정해석을 수행하였다. 연구결과 옹벽의 붕괴는 부적절한 뒤채움흙 및 설계, 장기강우 등의 복합적인 원인에 기인하는 것으로 검토 되었다. 본 논문에서는 옹벽의 설계 및 시공, 각종 조사 결과를 제시하였으며 이들을 종합하여 실무적 측면에서의 중점 고려사항을 다루었다.

Keywords

References

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