Stiffness and strength parameters for the hardening soil model of a reconstituted diatomaceous soil

• Published in: European journal of environmental and civil engineering 2023-01, Vol.27 (1), p.479-499
• Main Authors: Pérez León, Raimundo Francisco, Rodríguez Rebolledo, Juan Félix, Caicedo Hormaza, Bernardo
• Format: Article
• Language: English
• Subjects: constitutive model validation; finite element method; Hardening soil model; oedometer test; reconstituted diatomaceous soil; triaxial test
• ISSN: 1964-8189; 2116-7214
• DOI: 10.1080/19648189.2022.2051077

Centrifuge modelling has been widely used to study the geotechnical behaviour of structures built on soft soils and to calibrate and validate numerical models. In the finite element method (FEM), the mechanical behaviour of the soils is established through a constitutive model, and the correct selection and calibration of its parameters are essential to obtain accurate results. In this article, the mechanical parameters of an artificial reconstituted soft soil proposed for centrifuge modelling are obtained, calibrated and validated for the hardening soil (HS) model based on laboratory test results. The reconstituted soil consists of 50% kaolin clay and 50% diatomaceous soil from Bogotá, Colombia. First, geotechnical characterization of the reconstituted soil is presented. The model preparation technique to generate the effective stress profile for the centrifuge model is described. The strength and compressibility parameters are obtained from CU triaxial tests and a one-dimensional consolidation test, respectively. Finally, the obtained parameters are calibrated via explicit numerical modelling using the FEM and the SoilTest module of Plaxis software. It is concluded that the reconstituted artificial soft soil proposed herein mimics most of the natural lacustrine deposits of soft soils worldwide and can be modelled using the HS model for FEM analyses.