사질토와 점성토가 교호하는 지반의 굴착공사시 보일링 안정성 평가

초록

With ongoing urbanization, the demand for underground space has increased, making the stability of ground excavation works increasingly critical. In alternating sand–clay ground, the risk of unexpected boiling phenomena is particularly high. In practice, Terzaghi’s simplified method and seepage analysis are commonly applied; however, the criteria for incorporating the cohesion of clay layers remain unclear, often resulting in under-design or overly conservative embedment depths. This study conducted seepage analysis of a construction site in Busan, incorporating permeability coefficients, seepage pressure locations, and clay cohesion. The results show that when the excavation bottom is composed of sand, the safety factor obtained from the simplified method is comparable to that from the seepage analysis, indicating the simplified method is suitable. However, when the excavation bottom is clay, the safety factor from the seepage analysis is lower, indicating the need for a more conservative design approach to ensure boiling stability.

키워드