과잉간극수압 소산에 따른 케이슨식 방파제의 침하 및 지반 개량 효과에 대한 수치해석적 연구

초록

Earthquakes are a major factor affecting the stability of marine structures, and liquefaction occurs in saturated sandy soils, causing damage such as settlement, tilting, and collapse of structures. The 2017 Pohang earthquake was the first case of liquefaction in South Korea, resulting in damages at Yeongilman Port, including caisson settlement (approximately 10cm), hinterland settlement (10–20cm), and horizontal displacement (less than 15cm). In seismic response analysis, undrained conditions are typically assumed; however, this approach has limitations as it fails to account for additional displacements occurring after the dissipation of excess pore water pressure. To address this issue, an analysis considering drained conditions is necessary. Therefore, this study investigates the liquefaction-induced damage under drained conditions considering the dissipation of excess pore water pressure and explores methods to mitigate damage through ground improvement. As a result, the stability of the caisson breakwater was secured by improving the sandy ground beneath the caisson.

키워드