smillmorel
3d809ca301
10 KiB
Example models
Pre-built .osmodel files plus the Python scripts that generate them.
Each one carries the case types the post-processing views need, so you
can exercise the GUI without defining materials, sections, loads, and
cases by hand.
Files
| Model | Nodes | Elements | Cases | Shows |
|---|---|---|---|---|
cantilever.osmodel |
6 | 5 | Static × 2, Modal | Point + distributed loads, force diagrams, deformed shape, mode shapes |
portal_frame.osmodel |
4 | 3 | Static, Modal, Transient | All Display features, smallest 3D |
space_frame_3d.osmodel |
12 | 16 | Static, Modal, Transient (5% damping) | 3D rendering, multiple modes, damped EQ time-history |
sdof_pushover.osmodel |
2 | 1 | Pushover, Modal | Monotonic pushover curve, HystereticMaterial |
portal_pushover.osmodel |
4 | 3 | Pushover, Modal | Fiber sections, BeamWithHinges, yielding pushover |
ex1a_canti2d.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | OpenSees Ex 1a, shared gravity + push + quake |
ex1b_portal2d.osmodel |
4 | 3 | Static preload, Pushover, Transient EQ | OpenSees Ex 1b elastic portal, distributed gravity |
ex2a_canti2d_elastic_element.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | Ex 2a cantilever, dimensions as named parameters |
ex2b_canti2d_inelastic_section.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | Ex 2b, aggregated axial+flexure section |
ex2c_canti2d_inelastic_fiber_section.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | Ex 2c, fiber section, coupled axial-flexure |
ex3_canti2d_elastic_element.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | Ex 3 elastic build, unit-scaled parameters |
ex3_canti2d_inelastic_section.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | Ex 3 aggregated-section build |
ex3_canti2d_inelastic_fiber_section.osmodel |
2 | 1 | Static preload, Pushover, Transient EQ | Ex 3 fiber-section build |
ex4_portal2d_elastic_element.osmodel |
4 | 3 | Static preload, Pushover, Transient sine | Ex 4 elastic portal, build/analysis split |
ex4_portal2d_inelastic_section.osmodel |
4 | 3 | Static preload, Pushover, Transient sine | Ex 4 aggregated-section portal |
ex4_portal2d_inelastic_fiber_section.osmodel |
4 | 3 | Static preload, Pushover, Transient sine | Ex 4 fiber-section portal |
ex1a_canti2d_eq.osmodel |
2 | 1 | Static preload, Transient EQ | Ex 1a gravity + base excitation only |
eigen_two_storey_shear_frame.osmodel |
6 | 6 | Modal | equalDOF floor constraints, shear-frame modes |
eigen_two_storey_one_bay_frame.osmodel |
6 | 6 | Modal | Chopra 10.5 frame, sway modes, no constraints |
concrete04_cantilever.osmodel |
2 | 1 | Static (gravity), Pushover | Concrete04 fiber section end-to-end |
Quick tour
1. Force diagrams — cantilever.osmodel
File → Open → cantilever.osmodel
Analyze → Cases → run "Tip-Load"
Display → Show Force Diagram → component "M3" → linear moment, max at fixed end (50 kN·m)
→ component "V2" → constant -10 kN along the whole span
→ component "N" → ~zero (no axial load)
→ component "T" → ~zero (no torsion → console hint, no diagram)
Display → Show Deformed Shape → cantilever curve
Load runs along global Y (perpendicular to the beam, horizontal plane). With the default 3D vertical-reference convention that lands on the V2 / M3 pair — the in-plane bending pair.
UDL variant, parabolic moment:
Analyze → Cases → run "Uniform-Load"
Display → Show Force Diagram → M3 → parabolic, max 25 kN·m at fixed end
→ V2 → linear, max 10 kN at fixed end
2. Mode shapes — space_frame_3d.osmodel
File → Open → space_frame_3d.osmodel
Analyze → Cases → run "Modal-6"
Display → Animate Mode Shape → mode 1 = X-sway, mode 2 = Y-sway
→ Play, scrub timeline, change scale
3. Time-history and hysteresis — space_frame_3d.osmodel
File → Open → space_frame_3d.osmodel
Analyze → Cases → run "EQ-4s" (~5-10 sec on a modern laptop)
Display → Time-History Plot
- Node 12 (roof corner) + DOF 1 (X displacement) → "Add trace"
- Node 9 + DOF 1 → second trace, compare phase
Display → Hysteresis Plot
- X = Node 12 / DOF 1, Y = Node 12 / DOF 3 → orbit
4. Pushover — sdof_pushover.osmodel
File → Open → sdof_pushover.osmodel
Analyze → Cases → run "Push-X"
Display → Show Pushover Curve
→ linear from origin, then softens through yield
Column stays elastic here. Real nonlinear hinges need BeamWithHinges + fiber sections; the machinery exists, the fiber-section editor is still rough.
5. Nonlinear pushover with fiber hinges — portal_pushover.osmodel
File → Open → portal_pushover.osmodel
Analyze → Cases → run "Push-X"
Display → Show Pushover Curve
→ linear stiffness, then yield plateau as base hinges form
→ peak base shear = concrete crushing + rebar yield
Columns are BeamWithHinges + FiberSections (concrete core, rebar layers) wrapped in a SectionAggregator for torsion.
6. Gravity + time-history chain — ex1a_canti2d_eq.osmodel
File → Open → ex1a_canti2d_eq.osmodel
Analyze → Cases → run "Earthquake"
Display → Time-History Plot
- Node 2 + DOF 1 (Ux) → tip horizontal response
- Node 2 + DOF 2 (Uy) → gravity should stay locked
Tiny model, exists for one reason: the standard transient recipe
static preload → loadConst reset → UniformExcitation transient
against a real ground-motion record in a PathTimeSeries.
7. OpenSees Ex 1a bundle — ex1a_canti2d.osmodel
File → Open → ex1a_canti2d.osmodel
Analyze → Cases → run "Push" or "Earthquake"
Display → Show Pushover Curve / Time-History Plot
Cantilever column with shared gravity preload and both lateral variants. Small benchmark for checking pushover and transient agree on the same geometry.
8. OpenSees Ex 1b bundle — ex1b_portal2d.osmodel
File → Open → ex1b_portal2d.osmodel
Analyze → Cases → run "Push" or "Earthquake"
Display → Show Pushover Curve / Time-History Plot
Elastic portal frame. Gravity comes from a distributed beam load instead of nodal loads, which is the whole point of keeping it around.
9. Ex 2a, parameter-driven — ex2a_canti2d_elastic_element.osmodel
File → Open → ex2a_canti2d_elastic_element.osmodel
Analyze → Cases → run "Push" or "Earthquake"
Display → Show Pushover Curve / Time-History Plot
Same physics as Ex 1a, but dimensions and derived quantities are named parameters instead of literals.
10. Ex 2b, aggregated section — ex2b_canti2d_inelastic_section.osmodel
File → Open → ex2b_canti2d_inelastic_section.osmodel
Analyze → Cases → run "Push" or "Earthquake"
Display → Show Pushover Curve / Time-History Plot
First nonlinear cantilever in the series. Separate axial and flexural uniaxial responses aggregated into one section on a force-based beam-column.
11. Ex 2c, fiber section — ex2c_canti2d_inelastic_fiber_section.osmodel
File → Open → ex2c_canti2d_inelastic_fiber_section.osmodel
Analyze → Cases → run "Push" or "Earthquake"
Display → Show Pushover Curve / Time-History Plot
Ex 2b's fiber counterpart. Coupled axial-flexure with concrete and steel assigned to fibers and rebar layers directly.
12. Ex 3 family — ex3_canti2d_*.osmodel
File → Open → ex3_canti2d_elastic_element.osmodel
Analyze → Cases → run "Push" or "Earthquake"
Same cantilever analyses on three build styles: elastic element, aggregated uniaxial section, fiber section. All unit-scaled.
13. Modal shear building — eigen_two_storey_shear_frame.osmodel
File → Open → eigen_two_storey_shear_frame.osmodel
Analyze → Cases → run "Modal-2"
Display → Animate Mode Shape
- mode 1 → stories sway in phase
- mode 2 → stories sway out of phase
Validates modal workflows on a model small enough to check by hand,
with equalDOF doing the shear-frame duty.
14. Modal frame, Chopra 10.5 — eigen_two_storey_one_bay_frame.osmodel
File → Open → eigen_two_storey_one_bay_frame.osmodel
Analyze → Cases → run "Modal-2"
Display → Animate Mode Shape
- mode 1 → in-phase sway of both stories
- mode 2 → top story reverses against the first
Companion to the shear building above. Ordinary beam-column behavior, no multi-point constraints.
15. Ex 4 portal family — ex4_portal2d_*.osmodel
File → Open → ex4_portal2d_elastic_element.osmodel
Analyze → Cases → run "Push" or "Sine-Uniform"
Display → Show Pushover Curve / Time-History Plot
Keeps the OpenSees split between model-building and analysis files, recast as project variants. Covers pinned-base sway, distributed girder gravity, and support-motion dynamics without an external quake file. The fiber transient is kept as a nonlinear stress test — it may stop early and still produce usable partial histories.
Regenerating the .osmodel files
Scripts are the source of truth, .osmodel files are build artifacts
checked in for convenience. Change a script, rerun it:
python examples/cantilever.py
python examples/portal_frame.py
python examples/space_frame_3d.py
python examples/sdof_pushover.py
python examples/portal_pushover.py
python examples/ex1a_canti2d.py
python examples/ex1b_portal2d.py
python examples/ex2a_canti2d_elastic_element.py
python examples/ex1a_canti2d_eq.py
python examples/ex2b_canti2d_inelastic_section.py
python examples/ex2c_canti2d_inelastic_fiber_section.py
python examples/ex3_canti2d_elastic_element.py
python examples/ex3_canti2d_inelastic_section.py
python examples/ex3_canti2d_inelastic_fiber_section.py
python examples/ex4_portal2d_elastic_element.py
python examples/ex4_portal2d_inelastic_section.py
python examples/ex4_portal2d_inelastic_fiber_section.py
python examples/eigen_two_storey_shear_frame.py
python examples/eigen_two_storey_one_bay_frame.py
Each script builds the project, saves it, reloads it, and asserts a clean round-trip.