A New Procedure for Determining Parameter Values in the Barcelona Basic Model

Abstract

Abstract. The Barcelona Basic Model (BBM) is one of the most popular elastoplastic models for unsaturated soils. However, determination of parameter values from experimental data is often not straightforward and this has hindered dissemination of the model among practitioners. The main difficulty is related to the calibration of the isotropic virgin response as individual aspects of soil behaviour are controlled in BBM by multiple parameters while a single parameter can control more than one aspect of soil behaviour. As a consequence, iterative calibration procedures are common practice, where parameter values are adjusted in turn to match experiments. These procedures require significant experience, are time consuming and often lead to different parameter values. In this context, a new calibration method for the isotropic virgin behaviour in BBM is proposed where each parameter is determined in a specific order without making assumptions on remaining ones. The procedure, which is objective, simple and robust, has the potential of increasing the appeal of BBM for practitioners.

Bearing capacity of shallow footing on an unsaturated embankment upon infiltration

“…Permeabilities of the soils were estimated using the method proposed in [17] for sand and using the methodology in [18] for HC and STC soils. Table 2 presents the BBM parameters and the permeability values for the three soils adopted during the analysis [19,20,[21][22][23].…”