The initial use of such pressure in design met with criticism, but field and laboratory evidence, which highlights its significance, continues to accumulate.A nonlinear rheological model is used to numerically simulate the consolidation process of clay in laboratory tests and to identify the basic mechanical parameters that contribute to the development of the quasi-preconsolidation phenomenon.
The combined methods were not tested for published data since matric potentials for measured values were unknown.These tests can be costly due to expensive equipment and the long period of time they require.Each sample must be undisturbed and can only undergo one test with satisfactory results.This point is within the range of probable preconsolidation pressures.It can be used in calculations that require less accuracy or if a rough estimate is all that is required.as the intersection of two lines: (a) the regression line obtained for the first two, three, four or five points of the applied stress sequence in the secondary compression portion of the compression curve and (b) the extension of the virgin compression line determined from the points associated with applied stress of 8 k Pa. The σ estimated using the graphical procedure of Casagrande for 288 soil compression curves from three soils in Michigan and from values reported in the literature.
Methods 1 and 5 fit our data best at low σ (0.92), and closeness of fit to the 1:1 line, a combination of methods 1 and 3 was selected as the best estimation procedure.
All of these require site evaluation before construction.
Preparing a site for construction requires an initial compression of the soil to prepare for foundation to be added.
See "Modeling Volume Change and Mechanical Properties with Hydraulic Models," from the Soil Science Society of America (link in references) for a more involved mathematical model based on Casagrande's method combining principles from soil mechanics and hydraulics.
Various different factors can cause a soil to approach its preconsolidation pressure: Preconsolidation pressure is used in many calculations of soil properties essential for structural analysis and soil mechanics.
One of the primary uses is to predict settlement of a structure after loading.