Non-local numerical modelling of riverbank stability during rainfall events

This study examines the stability of a near-vertical riverbank composed of homogeneous, highly over-consolidated, weakly cemented clayey silt in the event of prolonged rainfall. In the numerical study, a non-local modelling approach was employed to accurately reproduce the formation and propagation of the shear band that caused the bank to collapse. This approach was introduced at the constitutive level by modifying the constitutive equations of the WR2 model. The study demonstrates that the non-local approach is a valid tool for modelling instability mechanisms, providing solutions that are scarcely affected by mesh discretisation schemes, even in coupled boundary value problems. Furthermore, it confirms the necessity of incorporating regularisation techniques into numerical models for this class of boundary value problem, as conventional modelling approaches yield inaccurate, mesh-dependent predictions.