Finite Element Analysis of Rainfall Infiltration in a Compacted Loess Embankment

Abstract:

Because of evapo-transpiration, compacted loess road embankments were considered to be in a partially saturated state in both arid and semi-arid regions. Based on previous studies and the theory of unsaturated soil mechanics, a numerical analysis of rainfall infiltration in a compacted loess road embankment was conducted. The transient seepage characteristics and moisture migration patterns of the moisture in the embankment were analysed. The results showed that after precipitation, the moisture profile of the compacted loess could be separated into three zones .The data also showed that: under the effect of gravity, the water continued to migrate into the embankment after the rainfall had ended. In time, the saturated zone became partially saturated as the moisture content decreased, whereas the moisture content in the conducting and humid zones increased and the wetting front moved downward. The data also showed that the depth of the conducting and humid zones increased in time, but that the moisture content in the conducting zone increased along a linear gradient with depth, while the moisture content in the humid zone decreased in a similar manner.

• Periodical: Advanced Materials Research (Volume 936)
• Pages: 1511-1517
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.936.1511
• Online since: June 2014
• Authors: Qing Feng Lv*, Peng Fei Liu, Yan Xu Zhao
• Keywords: Compacted Loess, Finite Element Analysis (FEA), Infiltration, Moisture Content, Rainfall

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