Choong-Ki Chung

Ground cave-ins caused by damaged sewer pipes have been frequently reported in metropolitan areas and have caused severe socioeconomic losses. In this study, model experiments were conducted to determine how damaged sewer pipes generate ground cave-ins or cavities, with a focus on the influence of the soil type and density. Digital images of the model ground were captured to evaluate the internal deformation of the model grounds. Additionally, the vertical displacement at the surface, the size o

Abstract. In several countries, the rising occurrence of sinkholes has led to severe social and economic damage. Based on the mechanism of sinkhole development, researchers have investigated the correlation between rainfall intensity and sinkholes caused by damaged sewer pipes. In this study, the effect of rainfall intensity on the formation of eroded zones, as well as the occurrence of sinkholes caused by soil erosion due to groundwater infiltration through pipe defects, has been analyzed throu

Debris flows caused by heavy rainfall in mountain areas near expressways lead to severe social and economic losses and sometimes result in casualties. Therefore, the development of a real-time system for debris-flow hazard assessment is necessary to provide preliminary information for rapid decision making about evacuations or restoration measures, as well as to prevent secondary disasters caused by debris flows. Recently, various map-based approaches have been proposed using multi-attribute cri

지층 정보는 지반 특성을 파악하기 위해 근본적으로 활용되는 가장 중요한 지반 정보이다. 전체 대상지에 대한 지반 정보는 부지들의 제한적인 지반 조사 자료를 토대로 지구통계학적 방법인 크리깅을 적용하여 연속적으로 예측할 수 있다. 본 연구에서는 지형에 따른 지층의 급격한 변화 영향을 최소화하기 위해 표고 변화가 완만한 3개 평지를 대상으로 선택하여 각 대상지의 지층 정보를 다양한 방식으로 예측하고, 그에 따른 예측 오차를 분석하였다. 예측된 지층 정보는 평지의 일반적인 지형 특성과 일치하였으며, 이는 상부 지층인 충적토층 및 풍화잔류토층에서 두드러졌다. 또한, 지층 경계면 고도보다 지층 두께를 이용한 예측 기법의 정확도가 높았다. 그러나 예측된 지층 정보는 신뢰성에 한계가 있으므로, 오차 분석 결과와 함께 지반 조사시 예비 자료로서 활용하는 것이 바람직하다.

Pile foundations that support transmission towers or offshore structures are dominantly subjected to cyclic lateral load induced by wind and waves. For a successful design, it is crucial to investigate the effect of cyclic lateral loads on the pile behavior that is loaded laterally. Although the p–y curve method is generally utilized to design the cyclic laterally loaded pile foundations, the effect of cyclic lateral loads on the pile has not been properly implemented with the p–y curve. This re