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Internal soil erosion caused by water infiltration around defective buried pipes poses a significant threat to the long-term stability of underground infrastructures such as pipelines and highway culverts. This study employs a coupled computational fluid dynamics–discrete element method (CFD–DEM) framework to simulate the detachment, transport, and redistribution of soil particles under varying infiltration pressures and pipe defect geometries. Using ANSYS Fluent (CFD) and Rocky (DEM), the simulation resolves both the fluid flow field and granular particle dynamics, capturing erosion cavity formation, void evolution, and soil particle transport in three dimensions. The results reveal that increased infiltration pressure and defect size in the buried pipe significantly accelerate the process of erosion and sinkhole formation, leading to potentially unstable subsurface conditions. Visualization of particle migration, sinkhole development, and soil velocity distributions provides insight into the mechanisms driving localized failure. The findings highlight the importance of considering fluid–particle interactions and defect characteristics in the design and maintenance of buried structures, offering a predictive basis for assessing erosion risk and infrastructure vulnerability.
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This content will become publicly available on January 1, 2026
Developing Soil Internal Erosion Indicator to Quantify Soil Internal Erosion around Defective Buried Pipes under Water Exfiltration
- Award ID(s):
- 2451951
- PAR ID:
- 10612301
- Publisher / Repository:
- ASTM
- Date Published:
- Journal Name:
- Geotechnical Testing Journal
- ISSN:
- 0149-6115
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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