Constitutive model for overconsolidated clays

Abstract

Based on the relationships between the Hvorslev envelope, the current yield surface and the reference yield surface, a new constitutive model for overconsolidated clays is proposed. It adopts the unified hardening parameter, to which the potential failure stress ratio and the characteristic state stress ratio are introduced. The model can describe many characteristics of overconsolidated clays, including stress-strain relationships, strain hardening and softening, stress dilatancy, and stress path dependency. Compared with the Cam-clay model, the model only requires one additional soil parameter which is the slope of the Hvorslev envelope. Comparisons with data from triaxial drained compression tests for Fujinomori clay show that the proposed model can rationally describe overconsolidated properties.In addition, the model is also used to predict the stress-strain relationship in the isotropic consolidation condition and the stress paths in the undrained triaxial compression tests. overconsolidated clays, current yield surface, reference yield surface, unified hardening parameter, Hvorslev envelope.

Exploration of the polar microenvironment around the reactive cysteine in rabbit muscle creatine kinase

“…The preparation of rabbit muscle CK was as described before [28]. Purified CK was homologous on SDS-PAGE.…”

“…The kinetic equation of the complexing irreversible inactivation of creatine kinase. centration was determined by the absorbance at 280 nm with A 1% 1 cm = 8.8 [28]. ATP and creatine were purchased from Fluka (Fluka, St. Gallen, Switzerland), DTNB (CAS# 69-78-3), DTNA (CAS# 15658-35-2) and DSDP (CAS# 2127-03-9) were all from Sigma (Sigma-Aldrich, St. Louis, MO, USA).…”

“…Activity assay of CK was performed by the pH-colorimetry method [28]. One milliliter of reaction mixtures contained 24 mM creatine, 4 mM ATP, 5 mM MgAC 2 , and 0.01% thymol blue, in 5 mM Glycine-NaOH buffer.…”

A Fractal Model to Interpret Porosity‐Dependent Hydraulic Properties for Unsaturated Soils

“…e issue of the effects of porosity on the hydraulic properties of soil was perhaps first raised by Croney and Coleman [25] and then followed by Laliberte et al [26]. Recently, the study of the porosity effects on hydraulic properties of unsaturated soils has attracted much attention because of the rapid development of unsaturated soil mechanics involving hydromechanical coupling [28][29][30][31][32][33][34][35][36][37][38]. In the literature, a few approaches have been proposed to model the effect of soil porosity on SWRCs and HCFs.…”

Applicability of UH model to coarse-grained soil

“…Yao et al [14][15] proposed the three-dimensional unified hardening model for overconsolidated clays (the UH model), based on the relationship between the current yield surface and reference yield surface. The UH model can model many characteristics of overconsolidated clays well, including stress-strain relationships, shear dilatancy, strainhardening and softening, and stress path dependence behaviour.…”