Variable Stiffness
The soil stiffness can be specified to vary with depth. This property is defined in the dialog "Add new soils" by choosing "Modulus" - which can be constant or linear. Entering parameter KE ensures that the finite elements will be assigned an individual value of Elasticity modulus (or the Undrained elasticity modulus) depending on their depth (vertical distance from the terrain in the first construction stage) according to the equation
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where: | Eref | - | Modulus of elasticity on terrain [MPa] |
KE | - | Modulus increment per meter of depth [MPa/m] | |
h | - | Depth [m] |

Same approach is applied also in case of Unload/reload modulus. With the following equation
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where: | Eur,ref | - | Unload/reload modulus terrain [MPa] |
KEur | - | Modulus increment per meter of depth [MPa/m] | |
h | - | Depth [m] |