Stability Evaluation for Soft Clay Slope Based on 2-D and 3-D Finite Element Method Analysis

Abstract:

Slope stability for soft clay is a hard problem in practice. In this paper, 2D and 3D finite element method (FEM) based on elastoplastic model are used to calculate the stress and displacement distribution in the soft clay slope under gravity and uniform load at the slope top. Stability analyses indicate that 3D boundary effect varies with the stress level of the slope. When the slope is stable, end effect of 3D space is not remarkable. When the stability decreases, end effect occurs; when the slope is at limiting state, end effect reaches maximum. The failure mode will not be the same if the slope is under different stress states; furthermore, a standard to evaluate slope failure with FEM calculation is established. The slope failure form caused by accumulative load is different from that caused by slope strength insufficiency. The energy causing slope failure spreads preferentially along Y-Z section. When the failure resistance capability reaches the limiting state, the energy can extend along X-axis direction. The 3D effect of the slope under uniform load on the top is related to the ratio of load influence width to slope height, and the effect is remarkable with the decrease of the ratio.

• Periodical: Applied Mechanics and Materials (Volumes 405-408)
• Pages: 142-146
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.405-408.142
• Online since: September 2013
• Authors: Zu Wen Yan, Yan Yi Zhang
• Keywords: Elasto-Plastic Model, Finite Element Method (FEM), Slope Stability, Soft Clay, Three-Dimensional Effect

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