According to EN 1997-1 [1] 6.5.3, it is necessary to design failure by sliding in the foundation base if the load vector is not perpendicular to this surface.
Sliding
References
- European Committee for Standardization (CEN). (2014). Eurocode 7: Geotechnical Design – Part 1: General Rules, EN 1997-1:2014-03. Berlin: Beuth Verlag GmbH.