otko/docs/gap-analysis-gidopensees.md

Gap Analysis — OTKO vs gidopensees

Source: D:\GitHub\gidopensees (AUTh Lab of R/C and Masonry Structures) Scope: Material / section / element / constraint / load / damping schema coverage. Date: 2026-05-22

How to read this table

Column	Meaning
Category	Schema group (material family, element type, etc.)
Object	Name as it appears in gidopensees BOOK/CONDITION
OTKO name	Corresponding class in core/ (if any)
In Studio?	✅ fully supported · 🟡 partial · ❌ missing
In gidopensees?	✅ · ❌
Priority	P0 = already done · P1 = Phase 8 target · P2 = later

Priority rationale:

• P0 — already shipped; included for completeness.
• P1 — high-value for earthquake-engineering practice; aligns with Phase 8 roadmap items (isolators, Rayleigh per-region, confined concrete models, shell elements, floor diaphragm constraints).
• P2 — valid but lower-frequency in typical EQ-engineering workflows (soil p-y/t-z/q-z springs, 3-D solid elements, multi-yield plasticity, contact elements).

---

1. Uniaxial Materials

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Uniaxial / linear	Elastic	ElasticUniaxial	✅	✅	P0
Uniaxial / elastic-plastic	Elastic_Perfectly_Plastic	ElasticPP	✅	✅	P0
Uniaxial / elastic-plastic	Elastic_Perfectly_Plastic_with_Gap	—	❌	✅	P1
Uniaxial / damper	Viscous	—	❌	✅	P1
Uniaxial / damper	Viscous_Damper (Maxwell)	—	❌	✅	P1
Uniaxial / gap	Hyperbolic_Gap	—	❌	✅	P2
Uniaxial / soil	PySimple1	—	❌	✅	P2
Uniaxial / soil	TzSimple1	—	❌	✅	P2
Uniaxial / soil	QzSimple1	—	❌	✅	P2
Uniaxial / bond-slip	BondSP01	—	❌	✅	P2

2. Steel Uniaxial Materials

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Steel	Steel01	Steel01	✅	✅	P0
Steel	Steel02	Steel02	✅	✅	P0
Steel	Hysteretic	HystereticMaterial	✅	✅	P0
Steel	Reinforcing_steel (DoDD-Restrepo)	—	❌	✅	P1
Steel	Ramberg-Osgood_steel	—	❌	✅	P2

3. Concrete Uniaxial Materials

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Concrete	Concrete01_(Zero_tensile_strength)	Concrete01	✅	✅	P0
Concrete	Concrete02_(Linear_tension_softening)	Concrete02	✅	✅	P0
Concrete	Concrete04_(Popovics)	—	❌	✅	P1
Concrete	Concrete06	—	❌	✅	P2
Concrete	ConcreteCM (Chang-Mander)	—	❌	✅	P1

4. Combined Materials

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Combination	Series	—	❌	✅	P1
Combination	Parallel	—	❌	✅	P1
Combination	Section_Aggregator (in .mat)	SectionAggregator	✅	✅	P0

5. nD (Multi-dimensional) Materials

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
nD	Elastic_Isotropic	ElasticIsotropic	✅	✅	P0
nD	Elastic_Orthotropic	—	❌	✅	P2
nD	J2Plasticity	—	❌	✅	P2
nD	Damage2p	—	❌	✅	P2
nD	PressureIndependMultiYield	—	❌	✅	P2
nD	PressureDependMultiYield	—	❌	✅	P2
nD	PressureDependMultiYield02	—	❌	✅	P2
nD	Contact	—	❌	✅	P2

6. Sections

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Section	Elastic_Section	ElasticSection	✅	✅	P0
Section	Fiber	FiberSection	✅	✅	P0
Section	Fiber_Custom	FiberSection (manual fibres)	🟡	✅	P0
Section	FiberInt (interaction P-M)	—	❌	✅	P1
Section	Plate_Fiber	—	❌	✅	P2
Section	Elastic_Membrane_Plate	—	❌	✅	P2
Section	LayeredShell	—	❌	✅	P2
Section	Section_Aggregator	SectionAggregator	✅	✅	P0

7. Beam-Column Elements

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Frame	Elastic_Beam-Column	ElasticBeamColumn	✅	✅	P0
Frame	Elastic_Timoshenko_Beam-Column	—	❌	✅	P1
Frame	Force-Based_Beam-Column	ForceBeamColumn	✅	✅	P0
Frame	Displacement-Based_Beam-Column	DispBeamColumn	✅	✅	P0
Frame	Flexure-Shear_Interaction_DispBeamColumn	—	❌	✅	P2
Frame	BeamWithHinges	BeamWithHingesElement	✅	❌	P0

8. Truss Elements

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Truss	Truss	TrussElement	✅	✅	P0
Truss	Corotational_Truss	CorotTrussElement	✅	✅	P0

9. Surface / Plate Elements

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Surface	Quad	QuadElement	✅	✅	P0
Surface	Shell (ShellMITC4 / MITC4)	—	❌	✅	P1
Surface	ShellDKGQ	—	❌	✅	P1
Surface	Tri31	—	❌	✅	P2
Surface	QuadUP (u-p pore pressure)	—	❌	✅	P2

10. Solid Elements

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Solid	Standard_Brick_Element	—	❌	✅	P2

11. Zero-Length / Special Elements

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Special	Auto_Zero_Length (per-DOF uniaxial)	ZeroLengthElement	✅	✅	P0
Special	Auto_equal_constraint (auto equalDOF)	EqualDOFConstraint	✅	✅	P0
Special	ZeroLengthSection	ZeroLengthSectionElement	✅	❌	P0
Special	BeamContact (master/slave)	—	❌	✅	P2

12. Restraints (Boundary Conditions)

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Restraint	Point_Restraints	Node.restraint (6-tuple)	✅	✅	P0
Restraint	Line_Restraints (auto-apply to nodes on line)	—	❌	✅	P2
Restraint	Surface_Restraints (auto-apply to nodes on surface)	—	❌	✅	P2

13. Nodal Loads & Displacements

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Load	Point_Forces	NodalLoad	✅	✅	P0
Load	Line_Forces (nodal, along a line)	—	❌	✅	P2
Load	Surface_Forces (nodal, on a surface)	—	❌	✅	P2
Load	Line_Uniform_Forces	UniformElementLoad	✅	✅	P0
Load	Point_Displacements (imposed)	—	❌	✅	P1
Load	Line_Displacements (imposed, on nodes along line)	—	❌	✅	P2
Load	Surface_Displacements (imposed, on nodes on surface)	—	❌	✅	P2

14. Ground Motions

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Ground motion	Point_Ground_Motion_from_Record	PathTimeSeries + UniformExcitationPattern	✅	✅	P0
Ground motion	Point_Sine_Ground_Motion	— (no TrigTimeSeries)	❌	✅	P1
Ground motion	Records (BOOK 8 — ground motion file library)	PathTimeSeries.file_path (single file, no library)	🟡	✅	P1

15. Constraints

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Constraint	Point_Equal_constraint (master + slave)	EqualDOFConstraint	✅	✅	P0
Constraint	Line_Equal_constraint (slave nodes on line)	—	❌	✅	P1
Constraint	Point_Rigid_link (Bar / Beam)	—	❌	✅	P1
Constraint	Line_Rigid_link (slave nodes on line)	—	❌	✅	P1
Constraint	Point_Rigid_diaphragm (master + slave, XY/YZ/ZX plane)	—	❌	✅	P1
Constraint	Line_Rigid_diaphragm (slave nodes on line)	—	❌	✅	P1

16. Mass

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Mass	Point_Mass	node mass (Properties dock + SetMassCommand)	✅	✅	P0
Mass	Line_Mass (auto-lump to nodes)	—	❌	✅	P1
Mass	Surface_Mass	—	❌	✅	P2
Mass	Volume_Mass	—	❌	✅	P2

17. Rayleigh Damping

Category	Object (gidopensees)	OTKO name	In Studio?	In gidopensees?	Priority
Damping	Global αM + βK (TransientCase fields)	TransientCase.rayleigh_alpha_m/beta_k	✅	🟡	P0
Damping	Mode-1 stiffness-proportional βK auto-compute	TransientCase.rayleigh_mode1_damping	✅	❌	P0
Damping	Per-region Rayleigh (Line/Surface/Volume/Point)	—	❌	✅	P1

---

Summary

Status	Count
✅ Fully in OTKO	34
🟡 Partial	3
❌ P1 targets (Phase 8 additions)	23
❌ P2 deferred	21

Top P1 targets (highest EQ-engineering impact, not in Studio yet):

1. ElasticPP_with_Gap — bearing pad / isolation gap nonlinearity
2. Viscous / Viscous_Damper — supplemental damping devices
3. ReinforcingSteel — DoDD-Restrepo model for well-detailed rebar
4. Concrete04 (Popovics) / ConcreteCM (Chang-Mander) — better confined concrete
5. Series / Parallel — material combination building blocks for isolation systems
6. RigidDiaphragm — floor slab constraint, essential for 3D building models
7. RigidLink — column/beam offset rigid connections
8. Shell (MITC4 / ShellDKGQ) — wall / slab elements
9. FiberInt — P-M interaction section for axial-flexure coupling
10. PointDisplacement imposed load — displacement-based loading at nodes
11. Per-region Rayleigh damping — finer damping control for mixed models
12. Sine ground motion / ground motion record library — GM workflow completion