Impact of Piping Erosion Process on the Temporal–Spatial Mechanisms of Soil

Abstract

Earthen dams with greater fines are more susceptible to failure from the piping. This study employed the coupled computational fluid dynamics (CFD)-discrete element method (DEM) to investigate the impact of the piping erosion process. Results displayed that increasing the fine contents would reduce the particle velocity and drag force for enhancing the erosion resistance. Piping would reduce the stability of the structure at different positions of the sample with various fine contents. The representative volume elements (RVE) were selected to observe the local geometry and material behavior as the erosion progressed. Severe water flows significantly reduced the peak shear strength of the eroded soils for the interactive-underfilled soil, particularly for the downstream side. However, the interactive-overfilled specimen reduced the peak shear strength on the upstream side. Results indicated that the proposed weighted clustering coefficient is a better index to capture the shear strength of the eroded soil matrix, with a high magnitude corresponding to a high peak shear strength. Different local material behavior may lead to differential settlements and associated catastrophic consequences during the piping erosion process, which should draw special attention.