GRANULOMETRIC LIMITS OF HYPOPLASTIC MODELS

Abstract

Several successful applications of the hypoplastic models would not be possible without a reliable and simple calibration procedure of the model parameters. The procedure utilizing standard properties of grain assemblies is well-suited for sands and is briefly outlined here. How ever, there are limits for the application of this approach for other soils. This is demonstrated for a coarse-grained limestone rockfill and a lined-grained loess. Whereas the parameter determination of the limestone rockfill is mainly limited by the available laboratory equipment, the calibration procedure must be significantly modified for the loess soil. Finally, a serious problem concerning the application of the hypoplastic model for soils with low friction angles is discussed. It is shown that in this case the ratio of incremental stiffness moduli in triaxial and isotropic compression is unrealistically low.