DDM-Based Response Sensitivity Computation Tcl Commands:

Created by: Quan Gu (Xiamen University, China), Joel P. Conte (UCSD), Michele Barbato (LSU), Yong Li (UCSD)

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Return to Sensitivity Analysis User Page

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• Sensitivity_Command_Manual
  • General Commands
    • reliability
    • parameter
    • addToParameter
    • updateParameter
    • sensitivityIntegrator
    • sensitivityAlgorithm
    • recorder
  • Material Commands
    • uniaxialMaterial
    • nDmaterial
  • Section Commands
    • Fiber
    • Elastic
    • Aggregator
  • Element Commands
    • dispBeamColumnWithSensitivity
    • quadWithSensitivity
    • bbarBrickWithSensitivity
  • Constraint Commands
    • Transformation

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Introduction

The following Analysis commands are added to the interpreter to create the Analysis and perform the analysis:

General Commands

reliability Command

This command creates the reliability domain in which the sensitivity, reliability and optimization components are kept. This reliability domain is parallel to the finite element (FE) domain in OpenSees. Currently, the commands for stand-alone sensitivity analysis (e.g., sensitivityIntegrator, sensitivityAlgorithm) are set in the reliability domain only and, thus, the ‘reliability’ command must be used before any stand-alone sensitivity analysis.

parameter Command

In DDM-based FE response sensitivity analysis, the sensitivity parameters can be material, geometry or discrete loading parameters.

addToParameter Command

In case that more objects (e.g., element, section) are mapped to an existing parameter, the following command can be used to relate these additional objects to the specific parameter.

updateParameter Command

Once the parameters in FE model are defined, their value can be updated.

sensitivityIntegrator Command

Define the sensitivity integrator.

sensitivityAlgorithm Command

Define the sensitivity algorithm.

recorder Commands

To record the nodal response and response sensitivity.

Material Commands

uniaxialMaterial commands

Several uniaxial materials are available for DDM-based FE response sensitivity computation.

SteelMP Material

This command is used to construct a uniaxial Menegotto-Pinto steel material object.

SmoothPSConcrete Material

This command is used to construct a uniaxial smoothed Popovics-Saenz concrete material object.

UniaxialJ2Plasticity Material

This command is used to construct a uniaxial J2 Plasticity material object with isotropic and kinematic hardening.

Hardening Material for Sensitivity

This command is used to construct a uniaxial material object with combined linear kinematic and isotropic hardening.

Concrete01 Material

This command is used to construct a uniaxial Kent-Scott-Park concrete material object with degraded linear unloading/reloading stiffness according to the work of Karsan-Jirsa and no tensile strength (refer to http://peer.berkeley.edu).

Steel01 Material for Sensitivity

This command is used to construct a uniaxial bilinear steel material object with kinematic hardening and optional isotropic hardening described by a non-linear evolution equation (refer to http://peer.berkeley.edu).

Elastic Material

This command is used to construct a linear elastic uniaxial material object (with optional material damping).

nDmaterial commands

Currently, only one multi-axial material model has been extended for DDM-based FE response sensitivity computation.

MultiYieldSurfaceClay

The ‘MultiYieldSurfaceClay’ is an elastic-plastic material in which plasticity exhibits only in the deviatoric stress-strain response. The volumetric stress-strain response is linear-elastic and is independent of the deviatoric response. This material is implemented to simulate monotonic or cyclic response of materials whose shear behavior is pressure independent. Such materials include, for example, organic soils or clay under fast (undrained) loading conditions.

This material is available for sensitivity computation in both 2-D and 3-D models. It is another version of PressureIndependMultiYield material. However there are three differences between this model and PressureIndependMultiYield:

1. This model uses the consistent tangent modulus instead of the continuum tangent modulus.

2. This model does not support the ‘updateMaterialStage’ command.

3. This model does not support further discretization of the strain increment in each iteration.

Section Commands

Currently, only two cross-section models and the section aggregator have been extended for DDM-based FE response sensitivity computation.

Section Commands

Fiber

Both 2-D and 3-D fiber sections are available for response sensitivity computation.

Elastic

Both 2-D and 3-D elastic sections are available for response sensitivity computation.

Aggregator

This command is used to construct a SectionAggregator object which groups previously-defined UniaxialMaterial objects into a single section force-deformation model.

Element Commands

Currently, several element types have been extended for DDM-based FE response sensitivity computation.

Element Commands

dispBeamColumnWithSensitivity

This command is used to construct a 2-D or 3-D distributed-plasticity displacement-based beam-column (frame) element.

quadWithSensitivity

This command is used to construct a 2D four-node quadrilateral element object based on a bilinear isoparametric formulation.

bbarBrickWithSensitivity

This command is used to construct an eight-node 3D brick element object based on a trilinear isoparametric formulation.

Constraint Commands

Currently, several element types have been extended for DDM-based FE response sensitivity computation.

Constraint Commands

Transformation

This command is used to construct a multi-point constraint handler based on the transformation equation method.