Modeling and experimental validation of crack-induced bottom-side erosion effects in buried pipelines

• Crack effects are incorporated into a pipe-soil interaction (PSI) model for buried pipes. • A novel lab setup simulates bottom-side erosion and captures real-time pipe deflection, and experimental results validate model accuracy. • Sensitivity analysis reveals burial depth, pipe size, and K 2 strongly influence deflection. Bottom-side erosion of buried pipelines can lead to the formation of surrounding cavities and ultimately cause pipeline failure. However, studies on external erosion lack sufficient experimental validation, and existing models often inadequately account for cracks and boundary conditions. This study integrates the Euler beam theory with Winkler and Pasternak foundation models to establish a theoretical pipe-soil interaction (PSI) model. A torsional spring is introduced to simulate cracks and optimize boundary conditions. Laboratory experiments are conducted to replicate various erosion scenarios, verify model applicability, and perform parameter sensitivity analyses. Results show that the Pasternak model offers higher prediction accuracy. The presence of cracks significantly increases pipeline deflection. Parameters such as pipe diameter and burial depth markedly affect deflection. This research enhances the theoretical understanding of PSI under bottom-side erosion and provides a foundation for pipeline safety assessment.