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Initial conditions, Type=stress

*Initial conditions, Type=stress, <option>`
<element set>, <ic parameter 1>, ..., <ic parameter n>
Specify the initial values of initial stress at the integration points of an element or element set. Use one of the following options:

  • Homogeneous

    use this option to prescribe a homogeneous distribution of initial stress for a particular element set. The command line takes the following form:

    *Initial Conditions, Type = stress, Homogeneous

    <element set name>, sigma_{xx,0}, sigma_{yy,0}, sigma_{zz,0}

  • Geostatic
    Use this option to assign an elevation-dependent initial stress field to all members of a given element set. When a geostatic stress is prescribed for a particular element set, the stress in the vertical direction \(h\) (assumed to be the \(z\)-direction in 3-D and axisymmetric models and the \(y\)-direction in 2-D models) is assumed to vary piecewise linearly with this vertical coordinate. The command line takes the following form:

    *Initial Conditions, Type = stress, Geostatic

    <element set name>, h_1, sigma_0(h_1), h_2, sigma_0(h_2), K_{x,0}, K_{y,0}

    \(K_{x,0}\) and \(K_{y,0}\) are the lateral stress coefficients.

  • Full

    use this option to prescribe each component of the initial stress for a particular element set. The command line takes the following form:

    *Initial Conditions, Type = stress, Full

    <element set name>, sigma_{xx,0}, sigma_{yy,0}, sigma_{zz,0}, sigma_{xy,0}, sigma_{xz,0}, sigma_{yz,0}

  • User

    Use this option to specify the use of a user defined subroutine to define the initial stress field:

    *Initial Conditions, Type = stress, User

    The required user routine is described here.