Consolidation theories

The Dave model considers a force balance on a porous medium (the fiber bed). The total force from the autoclave pressure acting on the medium is countered by both the force due to the springlike behavior of the fiber network and the hydrostatic force due to the liquid resin pressure within the porous fiber bed. Borrowing from consolidation theories developed for the compaction of soils [23,24], the Dave model describes one-dimensional consolidation... 

A generalized three-dimensional resin flow model has been developed that employs soil mechanics consolidation theory to predict profiles of resin pressure, resin flow velocity, laminate consolidation, and resin content in a curing laminate. 

Zhao (1994) presented a model of coupled coal deformation and methane migration based on a consolidation theory of elastic medium with Darcy fluid flow and the Terzaghi effective stress law, and its numerical solution technique and applications to practical problems. Works using similar approaches were also reported in Liang et al. (1995,1996), Sun and Xian (1999), Ding et al. 

Abstract A united mathematical model for the rheological and transport properties of saturated clays is proposed. The foundation of the model is the unification of filtration s consolidation theory and the theory of the stability of lyophobic colloids, which is based on the conception of disjoining pressure as a surplus in relation to hydraulic pressure. This pressure is caused by surface capacities and exists in water films between clay particles. In this work it is shown that the problem of the shrinkage of a clay layer can be reduced to the well known problem. We obtained the approximate solution for pressing the water out of a clay layer. The solution that we obtained requires introduction of a concept for the limit shear stress for clays. We investigated the model, and explained some characteristic features of transfer processes in clays (the existence of anomalous high pressures in clays, the flocculation at diffusion in clays, etc.). It is shown that solutions which we received are in harmony with results of experiments. 

Biot (1941) derived the 3-D consolidation theory, which describes the coupled hydraulic and mechanical transient response of a linear elastic, isotropic, homogeneous porous medium. One aspect of his theory is the effective stress law for elastic deformation ... 

Permeability can also be determined from the normal consolidation test. The permeability of a saturated sample undergoing consolidation under a load is used to model the dissipation of pore pressure with time (Terzaghi, 1925,1943). The coefficient of permeability (k) is a function of the coefficients of consolidation (Q) and volume compressibility (mj which arise from one-dimensional consolidation theory. 

Comparison of permeability values measured in the laboratory, and computed from consolidation tests have been reported by Nickerson (1978) and Olsen and Daniel (1979). In addition, Nickerson and Olsen and Daniel both show that the direct determination of permeability gives higher values than back-calculating values from consolidation tests. Nickerson suggests that the discrepancy between the direct determination of permeability in the laboratory and back calculated from the consolidation test are due to the variation of hydraulic gradients and/or the formation of a filter cake at the sediment-porous stone interface during consolidation. Olsen and Daniel (1979) attribute at least part of the discrepancy to the fact that Terzaghi s consolidation theory makes no adjustment for the structural viscosity (creep) of the soil. However permeability derived from one-dimensional consolidation tests may provide sufficiently accurate information for preliminary analyses. 

Helm, D.C. 1987. Three-dimensional consolidation theory in terms of the velocity of solids. Geotechnique 37(3) 369-392. 

The total amount of settlement due to primary consolidation can be estimated using Terzaghi s onedimensional consolidation theory (Terzaghi 1943 Lambe and Whitman 1969 Peck et al. 1974 Terzaghi et al. 1996) as follows ... 

Soil is a mixture of a solid phase, a liquid phase (i.e., water) and a gaseous phase. Saturated soil is a two-phase material which consists of a solid phase and a liquid phase. The formulation of a theory for a saturated soil commenced with the concept of the effective stress of Terzaghi at the beginning of the twentieth century, and Terzaghi s concept was extended by Biot to a three dimensional consolidation theory. 

Conservation of Linear Momentum, Effective Stress and Biot s Consolidation Theory... 

Gibson et al. (1967) proposed an alternative ID consolidation theory under a finite strain condition however, if we ignore a volume change due to the deformation process of the solid skeleton, the consolidation theory is not completely correct. We present a finite strain ID consolidation equation based on the finite strain consolidation theory described in Sect. 6.3. 

MD/HA Seepage Analysis and ID Consolidation Theory then the permeability k is obtained as... 

Vertical (Primary) Consolidation Terzaghi s one-dimensional consolidation theory ... 

If Sv and 5h (Fig. 13.18) are different, either the axisymmetric or the plane strain consolidation theory may not provide a satisfactory solution. Based on a series of numerical analysis results, Chai et al. (2014) proposed that by modifying the value... 

In the case of vacuum consolidation using PVDs, there may be a situation in which a soil layer adjacent to the PVDs becomes unsaturated. Consolidation theory under this kind of situation may need to be developed. 

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