ABSTRACT
In geotechnical engineering context inverse modelling or back analysis consists in finding the values of the mechanical parameters, or of other quantities characterizing a soil or rock mass, that when introduced in the stress analysis of the problem under examination lead to results (e.g. displacements, stresses etc.) as close as possible to the corresponding in situ measurements. The optimal state of the system is obtained by minimizing the difference between the observed values in the system and the forecasted or modelled state of the system within a certain time interval. In the eighties and the nineties, several articles concerning inverse analysis in geo-mechanics using the Maximum Likelihood and the (Extended) Bayesian method were published (Gens et al. 1996, Honjo et al. 1994a,b). Recent developments in other fields of science have shown a new powerful technique indicated as the Ensemble Kalman filter. In a filter, the state of the system is analysed each time data becomes available.
