OpenSees.exe User Requirements

Implemented Requirements

Element

• Beam-Column Elements
• Truss Elements
• 2D Wall Elements

Section

• Elastic Section
• Fiber Section
• Section Aggregator
• Elastic Membrane Plate Section
• Plate Fiber Section
• Bidirectional Section
• Isolator2spring Section: Model to include buckling behavior of an elastomeric bearing

uniaxialMaterial

• Steel & Reinforcing-Steel Materials
  • Steel01 Material
  • Steel02 Material -- Giuffré-Menegotto-Pinto Model with Isotropic Strain Hardening
  • Hysteretic Material
• Concrete Materials
  • Concrete01 Material -- Zero Tensile Strength
  • Concrete02 Material -- Linear Tension Softening
  • Concrete03 Material -- Nonlinear Tension Softening
• Multi-Purpose Materials
  • Elastic Material
  • Elastic-Perfectly Plastic Material
  • Elastic-Perfectly Plastic Gap Material
  • Elastic-No Tension Material
  • Parallel Material
  • Series Material
  • Hardening Material
• Contributed uniaxialMaterial
  • BARSLIP Material
  • Bond_SP01 - - Strain Penetration Model for Fully Anchored Steel Reinforcing Bars
  • Concrete04 Material -- Popovics Concrete Material
  • Concrete07 – Chang & Mander’s 1994 Concrete Model
  • Fatigue Material
  • Hyperbolic Gap Material
  • Limit State Material
  • PINCHING4 Material
  • PyTzQz uniaxialMaterials
  • Reinforcing Steel Material
  • SelfCentering Material – Flag-Shaped Hysteresis with Slip Deformation and Bearing
• Elastic Isotropic Material
• J2 Plasticity Material
• Plane Stress Material
• Plate Fiber Material
• UCDavis Soil Models
  • Template Elasto-Plastic Material
• UCSanDiego Soil Models
  • FluidSolidPorousMaterial
  • PressureDependMultiYield Material
  • PressureDependMultiYield02 Material
  • PressureIndependMultiYield Material
  • updateMaterialStage
  • updateParameter

Recorder

• Node
  • Node
  • EnvelopeNode
  • Drift
• Element
  • Element
  • EnvelopeElement
• Section
  • Element
  • EnvelopeElement
• Fiber
  • Element
  • EnvelopeElement
• Basic Visualization recorders
  • Display
  • Plot
  • playback Command

Other

• Input Motion
  • Input displacement history in UniformExcitation Pattern Command
  • Input acceleration history in MultipleSupport Pattern Command

Under-Development Requirements

Element

• 2D/3D Wall Elements
• 3d nonlinear frame element with full interaction
  • axial
  • flexure
  • torsion
  • shear

Material

• Improved concrete materials
• Improved reinforcing-steel materials

To-Be-Developed Requirements

Element

• Buckling-Brace Elements
• Flexible Diaphragm
• 2D & 3D Isolators
• 2d Timoshenko beam element
• 3d frame element with bond-slip of reinforcing steel
• 3d frame element with slip between components, e.g. composite beam, composite column
• 3d concentrated plasticity element with return map algorithm
• 2d SIZE (spreading inelastic zone) beam element
• Nonlinear geometry developments
  • Extension of corotational theory to membranes and shells
  • Reformulation of 3d frame nonlinear geometry such that any element can take advantage of nonlinear transformation (currently not the case); quaternions vs. rotation nodal variables require either a change in global solution strategy or the mapping back and forth between quaternions and node rotations.
• The following elements include linear or corotational geometry for membranes and shells under large displacements
  • 3 to 6 node triangle
  • 4 to 9 node quad
  • 4 node quad with incompatible modes
  • 4 to 9 node RC panel (quad)
  • 4 to 9 node Mindlin layer plate/shell
  • 4 to 9 node Mindlin RC layer plate/shell
  • Discrete Kirchoff triangle plate/shell element

Section

• 2d normal and shear stress interaction

Material

• 3d J2 plasticity with kinematic and isotropic hardening
• 3d plastic-damage concrete constitutive model Lee-Fenves

Recorder

• Specify recorder to save only every Nth timestep (specifying dT only works for time-history analyses)
• EnvelopeDrift Node recorder

Other

• improved domain-data output

Continual-Development Requirements

Documentation

• Validation with experimental data
• Materials
  • Graphical demonstration of input-arguments
• Examples manual
  • Practical Examples
• Theoretical Background

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