Transient Unsaturated Seepage and Stability of a Homogeneous Earth Dam: A Case Study

DOI

10.2991/978-94-6239-703-3_7How to use a DOI?

Keywords

earth dam; unsaturated seepage; rapid drawdown; stability evolution

Abstract

Rapid reservoir level fluctuations drive transient seepage evolution in earth dams and induce redistribution of stress and deformation, thereby affecting slope stability. This study investigates a homogeneous earth dam in a small reservoir using a two-dimensional finite element model. Transient seepage in unsaturated media is simulated with a governing formulation parameterised by the van Genuchten soil-water retention relationship, and stability is evaluated using the strength reduction method based on the seepage results. Three representative scenarios are considered: the normal water level (108.5 m), rapid drawdown (108.5 m to 101.0 m at 0.5 m/d), and storm-driven rapid rise (108.5 m to 109.5 m at 0.5 m/d). During drawdown, pore water pressure along the upstream slope decreases while effective stress within the dam generally increases. Deformation concentrates near the upstream side under drawdown, whereas rapid rise produces a more pronounced downstream displacement response over a broader region. The factor of safety exhibits a non-monotonic trend during drawdown, increasing slightly from 1.92 to 1.96 before dropping rapidly to 1.02 at 101.0 m, with the critical slip surface predominantly developing on the downstream side. The results provide practical implications for reservoir operation and monitoring of small and medium-sized earth dams under rapid water-level changes.

Copyright

© 2026 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

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TY  - CONF
AU  - Yihan Yu
AU  - Bingkuo Song
PY  - 2026
DA  - 2026/06/08
TI  - Transient Unsaturated Seepage and Stability of a Homogeneous Earth Dam: A Case Study
BT  - Proceedings of the 2026 2nd International Conference on Engineering Management and Safety Engineering (EMSE 2026)
PB  - Atlantis Press
SP  - 61
EP  - 74
SN  - 2352-5401
UR  - https://doi.org/10.2991/978-94-6239-703-3_7
DO  - 10.2991/978-94-6239-703-3_7
ID  - Yu2026
ER  -