Centrifuge Model Experiments and Numerical Analyses of the Behavior of Excavated Marine Clay Slope

J. Ocean Eng. Technol. 2006;20(5):49-56.

Park, Byung-Soo;

G-1 Tech Co. Ltd.;

해성점토 굴착사면의 거동에 관한 원심모형실험 및 수치해석

박병수;

(주) 지완테크 지반공학부;

Keywords: Soft ground, Slope stability, Centrifugal model test, Replacement excavation

핵심용어: 연약지반, 사면안정, 원심모형실험, 굴착치환

Abstract

In this thesis, centrifuge model experiments and numerical analyses were carried out to investigate the behavior of an excavated slope in soft clay ground. Centrifuge model tests were performed with various slopes for the excavated ground, such as 1:1.5 and 1:2. Pore pressuresthe model ground were measured to find their effects on the stability of the excavated slope. These experiments showed that the model with 1:2.5 maintained its stability within a short period of time and failed gradually. Therefore, anexcavated slope of soft soil with this slope might maintain stable conditions within a certain time. The mode1 with a 1:3 slope was observed to maintain a very stable condition, showing insignificant deformation in the ground after being excavated. Numerical analyses with PLAXIS, a commerciallyavailable software implemented with the finite element numerical technique, were performed to find the pore pressure distribution within the ground mass and the deformation of the soil. From the results of numerical analysis, a negative pore pressure was developed after the excavation and thus the stability of the slope was maintained. The safety factor for slope failure was found to decrease with time because of the dissipation of negative pore pressure with time.