Material Parameters in Earthquake Analysis
The material parameters of soils needed in earthquake analysis are specified in the "Edit soil properties" dialogue window in Topology regime, the frame "Soils".
The dynamic modulus of elasticity corresponds to the elastic modulus at small strains. Its value is typically determined on the basis of field or laboratory measurements. Point out that the critical state constitutive models do not adopt the dynamic modulus in the formulation of the stiffness matrix.
Other parameters describe the material damping. In the GEO5 FEM program the Rayleigh damping is assumed. The damping matrix C is then defined as a linear combination of the mass matrix M and the stiffness matrix K as:
kde: | C | - | damping matrix |
M | - | mass matrix | |
K | - | stiffness matrix | |
α | - | Rayleigh parameter | |
β | - | Rayleigh parameter |
The Rayleigh parameters:
- are determined on the basis of the specified coefficient of proportional damping;
- can be specified directly.
Material parameters of soils needed for Earthquake analysis
Further details are available in the theoretical manual on our website.