13.2.2 Available user subroutines

Products: ABAQUS/Standard  ABAQUS/Explicit  ABAQUS/Aqua  



User subroutines allow advanced users to customize a wide variety of ABAQUS capabilities. Information on writing user subroutines and detailed descriptions of each subroutine appear online in the ABAQUS User Subroutines Reference Manual. A listing and explanations of associated utility routines also appear in that manual.

Available user subroutines

The available user subroutines for ABAQUS/Standard are as follows:

  • CREEP: Define time-dependent, viscoplastic behavior (creep and swelling).

  • DFLOW: Define nonuniform pore fluid velocity in a consolidation analysis.

  • DFLUX: Define nonuniform distributed flux in a heat transfer or mass diffusion analysis.

  • DISP: Specify prescribed boundary conditions.

  • DLOAD: Specify nonuniform distributed loads.

  • FILM: Define nonuniform film coefficient and associated sink temperatures for heat transfer analysis.

  • FLOW: Define nonuniform seepage coefficient and associated sink pore pressure for consolidation analysis.

  • FRIC: Define frictional behavior for contact surfaces.

  • GAPCON: Define conductance between contact surfaces or nodes in a fully coupled temperature-displacement analysis or pure heat transfer analysis.

  • GAPELECTR: Define electrical conductance between surfaces in a coupled thermal-electric analysis.

  • HARDINI: Define initial equivalent plastic strain and initial backstress tensor.

  • HETVAL: Provide internal heat generation in heat transfer analysis.

  • MPC: Define multi-point constraints.

  • ORIENT: Provide an orientation for defining local material directions or local directions for kinematic coupling constraints or local rigid body directions for inertia relief.

  • RSURFU: Define a rigid surface.

  • SDVINI: Define initial solution-dependent state variable fields.

  • SIGINI: Define an initial stress field.

  • UCORR: Define cross-correlation properties for random response loading.

  • UEL: Define an element.

  • UEXPAN: Define incremental thermal strains.

  • UEXTERNALDB: Manage user-defined external databases and calculate model-independent history information.

  • UFIELD: Specify predefined field variables.

  • UFLUID: Define fluid density and fluid compliance for hydrostatic fluid elements.

  • UFLUIDLEAKOFF: Define the fluid leak-off coefficients for pore pressure cohesive elements.

  • UGENS: Define the mechanical behavior of a shell section.

  • UHARD: Define the yield surface size and hardening parameters for isotropic plasticity or combined hardening models.

  • UHYPEL: Define a hypoelastic stress-strain relation.

  • UHYPER: Define a hyperelastic material.

  • UINTER: Define surface interaction behavior for contact surfaces.

  • UMASFL: Specify prescribed mass flow rate conditions for a convection/diffusion heat transfer analysis.

  • UMAT: Define a material's mechanical behavior.

  • UMATHT: Define a material's thermal behavior.

  • UMESHMOTION: Specify mesh motion constraints during adaptive meshing.

  • UMOTION: Specify motions during cavity radiation heat transfer analysis or steady-state transport analysis.

  • UMULLINS: Define damage variable for the Mullins effect material model.

  • UPOREP: Define initial fluid pore pressure.

  • UPRESS: Specify prescribed equivalent pressure stress conditions.

  • UPSD: Define the frequency dependence for random response loading.

  • URDFIL: Read the results file.

  • USDFLD: Redefine field variables at a material point.

  • UTEMP: Specify prescribed temperatures.

  • UTRACLOAD: Specify nonuniform traction loads.

  • UTRS: Define a reduced time shift function for a viscoelastic material.

  • UVARM: Generate element output.

  • UWAVE: Define wave kinematics for an ABAQUS/Aqua analysis.

  • VOIDRI: Define initial void ratios.

The available user subroutines for ABAQUS/Explicit are as follows:
  • VDLOAD: Specify nonuniform distributed loads.

  • VFRIC: Define frictional behavior for contact surfaces.

  • VUINTER: Define the interaction between contact surfaces.

  • VUMAT: Define material behavior.