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The quality and reliability of geotechnical design depends among other aspects on the quality of the chosen design method. This can be a simple analytical or empirical equation or a sophisticated numerical model with different degrees of complexity and accuracy in modeling the behavior of a geotechnical structure. However, exact modeling of the real behavior is impossible and the deviation of the predicted from the real behavior is expressed by the model uncertainty. According to eg Nadim (2015) model uncertainty is of epistemic nature as it is based on the simplifications, assumptions and approximations made in the respective design model. It therefore can be reduced by improving the model. Nadim (2015) also used the term transformation uncertainty for the uncertainties associated with the model as the model transfers input parameters to output parameters. A recent summary of geotechnical model uncertainty was presented by Dithinde et al.(2016). It should be explicitly noted, that model uncertainty in the context of this contribution and according to the definition given above only refers to the uncertainties of the applied calculation procedure or method. It shall not consider uncertainties from the overall geotechnical model which also includes the definition of the ground model and the related soil mechanical parameters used in the design. However, the model uncertainty often is intrinsically tied to these uncertainties as will be shown in the following. For the geotechnical engineering design practice, as considered by Eurocode 7, calculation models in many countries were calibrated on the basis of an overall factor of safety resulting from …