Simplifying calibration of bonded elasto-plastic models

Abstract

Using realistic constitutive models for artificially cemented soils is advantageous in design. However, the price of that increased realism is often a more elaborate model, which is difficult to calibrate. A database of high quality triaxial tests on compacted cemented silty sand is used to calibrate and validate a generalized critical state bonded soil model. The exercise highlights the staged calibration procedure that is convenient in this kind of application. The calibration results have shown a direct relation between added yield strength and a well-established soil-cement mixture ratio, which facilitates the application of the model in design. It is shown that such relation can be also deduced from the analysis of unconfined compressive strength tests.

Fragmentation modeling of a resin bonded sand

“…1. Adaptation of the Cemented Clay And Sand Model as described by Rios et al (2016). The model was modified to the resin-bonded sand by considering a linear elasticity, changing the damage law and the plastic flow rule 2.…”

“…The model highlighted here is adapted from the Clay And Sand Model (CASM) developped by Yu [1] and the cementention model developped by Gens and Nova [2]. This approach, called Cemented Clay And Sand Model (CCASM), has succesfully been applied to cemented sands (see Rios et al [3]). The model is calibrated and validated with the use of standard tests realized in collaboration with INSA of Lyon.…”

Data Pruning of Tomographic Data for the Calibration of Strain Localization Models

“…It consists in the extension of the Clay And Sand Model developed by Yu [39] for unbonded sand and clay to bonded geomaterials within the framework developed by Gens and Nova [40]. The C-CASM has been extensively described in [41]. The Modified Cemented Clay And Sand Model (MC-CASM) presented here has some modifications of the C-CASM:…”

Data Pruning of Tomographic Data for the Calibration of Strain Localization Models

“…A summary of the different matrix sizes at each step is displayed in Nova [35]. The C-CASM has been extensively described in Rios et al [36]. The Modified Cemented Clay And Sand Model (MC-CASM) presented here has some modifications of the C-CASM:…”

“…b = (−be −h + µ 6 µ 7 e −µ 7 h )ḣ (36) The incremental value of h is defined as a weighting of the effects of the incremental plastic shear strain and the incremental plastic volumetric strain:…”