Modified Cam Clay

The Modified Cam Clay model represents the hardening behavior of the elasto-plastic materials based on the critical state concept. The Modified Cam Clay model is similar to the Cam Clay model except that the yield function is in the shape of an ellipse instead of a tear drop. The critical state concept is ideal for the saturated remolded soil, which means that all the stress terms of the yield function represent not total but effective stresses.

Applicable Modules:

General Parameters

Modulus of Elasticity (E)

The slope of the stress-strain line for a linear isotropic material.

Poisson's Ratio (u)

The ratio of the radial (or lateral) strain to the vertical strain.

Temperature Coeff. (α)

The relative change of a physical property when the temperature is changed by 1 K.

Unit Weight (Υt)

The weight of soil per unit volume.

Saturated Unit Weight (Υsat)

The weight of saturated soil per unit volume.

Earth Pressure Coeff. (Ko)

The ratio of horizontal principal effective stress to the vertical principal effective stress.

Draining Condition

Drained

Dissipation of pore water pressure takes place upon the load application.

Undrained

Dissipation of pore water pressure does not take place upon the load application.

Skempton 'B' Coefficient

Enter the value of the coefficient for an 'Undrained' condition.

Hori. Permeability Coeff. (Kh)

The coefficient of permeability in horizontal direction.

Ver. Permeability Coeff. (Kv)

The coefficient of permeability in vertical direction.

Additional Parameters

Over Consolidation Ratio (OCR)

It is the ratio by which the current vertical effective stress in the soil was exceeded in the past.

Slope of N.C. Line (λ)

Slope of the Normal Consolidation line. It is related to Compression index by the relation

Slope of O.C. Line (K)

Slope of the Over Consolidation line. It is related to Compression index by the relation

Set Critical State

Select the Preconsolidation Void Ratio(ec) or Critical State Specific Volume(Γ )

Preconsolidation Void Ratio(ec)

Void ratio of preconsolidation state.

Critical State Specific Volume (Γ)

It is defined by 1+e

Slope of Critical State Line (M)

It is the slope of the Critical State Line and is related to the effective internal friction angle by the relation

The above terms can be noted in the figure shown below:

Pc Calculation Method

Select the one method among the Auto-calculation, Preconsolidation Pressure (Pc), Preconsolidation Vertical Stress (σc)

Auto-calculation

Preconsolidation Pressure (Pc) is automatically calculated by using initial stress and over consolidation ratio (OCR).

Preconsolidation Pressure (Pc)

Preconsolidation pressure (Pc) can be specified by user directly.

Preconsolidation Vertical Stress (σc)

Preconsolidation vertical pressure (σc) can be specified by user directly.