The calculation code SPHERA (RSE SpA), based on the Smoothed Particle Hydrodynamics (SPH) method, simulates the initiation and propagation phases of a full-scale embankment breach with coastal flooding. The code formulation adheres to the Kinetic Theory of Granular Flow (KTGF) and does not require input variable calibration. The primary landslide slip surface (LSS) within the embankment is reconstructed from the quadratic invariants of the strain rate tensor field.

Comparisons with experimental values of LSS position show maximum errors of 0.90m in terms of depth difference at a fixed planimetric point, and 0.41m in terms of LSS distance (i.e., 22% and 10% of the initial height of the embankment crest at the excavation bottom). Inter-comparisons performed for the initiation phase consider calibrated Finite Element Method (FEM) results. The criterion for identifying the LSS is defined and verified through analytical solutions and code validations on spherical Couette flows. Additionally, the impact on a virtual support of overhead power lines is evaluated. Code improvements and tutorials are available on github.com.