General Material(Behavioral properties)

 

Transversely Isotropic

Natural ground is generally layered and sloped, making it possible to have different strengths in each orthogonal direction. The figure below shows a soil layer with an angle   between the global x axis and the element x' axis and displays perpendicular anisotropy (orthotropy) with the x' axis and z' axis of the element.

 

<Orthotropic model>

This orthotropy is simulated by assigning different stiffness to the tangent and normal direction to the stratification (fault) orientation. Generally, the normal direction stiffness decreases in comparison to the tangential stiffness and the anisotropic shear strength is defined by the Shear modulus (G). For fully isotropic case,  , is equal to , respectively and G is defined by  .

 

Transversely isotropic materials are material models defined by an isotropic transverse section with a vertical axis to the section. The physical properties are the same within the transverse section and the vertical direction has different properties.

  • Out of transverse plane material properties :  , ,

  • In transverse plane material properties :  , ,

Here, is the Elasticity modulus in the vertical axis to the section,  , and ,  are the Poisson’s ratio and Shear modulus of the surfaces generated by the vertical and section with the other axes respectively.

The local coordinate system is defined by the dip angle  and dip direction . Because the reference axis of the inclined plane and horizontal plane ( and  respectively) are not identical, use the auxiliary angle that subtracts the declination (angle formed between the 2 axes) from when setting the actual transformation matrix.

Thermal

Conductivity: the ability to conduct thermal energy.

Specific Heat: the amount of heat required to raise single unit mass of a substance by single temperature unit. (required for transient heat transfer problems)

Heat Generation Factor: the value of the heat load multiplied by the exothermic coefficient used as the load vector for heat transfer analysis is the total exothermic load applied to the object.