kopaaParametric/ec3-steel-portal-frames

EC3 Steel Portal Frame Structural Analysis Dataset

Dataset Summary

A parametric structural analysis dataset of 995 single-span steel portal frames designed and verified to Eurocode 3 (EN 1993-1-1:2005). Each record represents a unique frame configuration solved with the Karamba3D 3.1 FEM solver inside Grasshopper / Rhinoceros 3D.

The dataset is intended for training and benchmarking AI models that predict structural performance, section selection, and code compliance in the early design phase of steel-framed buildings — industrial sheds, agricultural buildings, warehouses, and sports halls.

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Dataset Structure

Two linked JSONL files:

File	Records	Description
frames.jsonl	995	One record per frame — geometry, loads, global results
elements.jsonl	3 450	One record per structural element — section properties, utilization, internal forces

Frames and elements are linked via run_id (format: SF-00001 → SF-01000).

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Frame Schema

Each frame is a 2D single-span portal in one of two configurations:

Type	Count	Elements
Monopitch	530	2 columns + 1–2 rafters
Gable	465	2 columns + 2 rafters

Element identifiers: C1, C2 = columns; B1, B2 = roof beams (rafters)

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Parametric Ranges

Parameter	Range	Distribution
Span	5.0 – 25.0 m	Uniform random
Eaves height	3.0 – 10.0 m	Uniform random
Roof pitch	3.0 – 25.0°	Derived from geometry
Steel grade	S235 / S275 / S355 / S420 / S460	~200 frames each
Wind load	0.30 – 2.00 kN/m²	Uniform random
Snow load	0.30 – 4.00 kN/m²	Uniform random
Column profile family	HEB	Fixed
Rafter profile family	IPE	Fixed

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Key Statistics

Metric	Value
Total frames	995
Total elements	3 450
EC3 compliant frames	630 / 995 (63.3%)
Mean frame weight	4 036 kg
Frame weight range	323 – 11 799 kg
Mean element utilization	0.646
Utilization range	0.003 – 1.755
Governing load case	ULS_SnowLead (86.7%), ULS_WindLead (13.2%)
Governing EC3 check	My bending (93.3%), N axial (6.7%)
Mean monopitch rafter midspan deflection	112 mm
Mean gable rafter midspan deflection	47 mm

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Fields

frames.jsonl — 30 fields per record

Field	Type	Unit	Description
run_id	string	—	Unique frame identifier (SF-XXXXX)
design_code	string	—	EC3_EN1993-1-1_2005
solver	string	—	Karamba3D_3.1
roof_type	string	—	gable or monopitch
frame_schema	string	—	Frame topology identifier
span_mm	float	mm	Clear span between column bases
eaves_h_mm	float	mm	Eaves height
ridge_h_mm	float	mm	Ridge height
haunch_h_mm	float	mm	Vertical rise from eaves to ridge
slope_deg	float	degrees	Roof pitch angle
slope_pct	float	%	Roof pitch as percentage
rafter_length_mm	float	mm	True rafter length along slope
steel_grade	string	—	S235 / S275 / S355 / S420 / S460
col_profile_family	string	—	Column section family (HEB)
beam_profile_family	string	—	Rafter section family (IPE)
wind_kNm2	float	kN/m²	Characteristic wind pressure
snow_kNm2	float	kN/m²	Characteristic snow load
roof_sw_kgm2	float	kg/m²	Roof self-weight (cladding + purlins)
tech_load_kgm2	float	kg/m²	Imposed technical load on roof
max_col_defl_L	int	—	Column sway limit denominator (H/L)
max_beam_defl_L	int	—	Rafter deflection limit denominator (L/x)
frame_weight_kg	float	kg	Total steel weight of frame
max_horiz_defl_mm	float	mm	Maximum horizontal nodal displacement (all LCs)
max_vert_defl_mm	float	mm	Maximum vertical nodal displacement (all LCs)
roof_mid_vert_defl_mm	float	mm	Maximum vertical displacement at rafter midspan (all LCs)
n_elements	int	—	Number of structural elements
load_cases	list[str]	—	Names of all ULS load case combinations
is_ec3_compliant	bool	—	True if all elements util ≤ 1.0
nodes	list[dict]	—	Node coordinates and support flags
displacements	list[dict]	—	Nodal displacements per node per LC (mm)

elements.jsonl — 47 fields per record

Field	Type	Unit	Description
run_id	string	—	Links to parent frame
elem_id	string	—	Element identifier (C1, C2, B1, B2)
elem_type	string	—	column or rafter
node_start / node_end	int	—	Node indices
length_mm	float	mm	Element length
section	string	—	Profile name (e.g. HEB300, IPE400)
section_family	string	—	Profile family (HEB, IPE)
A_cm2	float	cm²	Gross cross-sectional area
Iyy_cm4	float	cm⁴	Second moment of area (strong axis)
Izz_cm4	float	cm⁴	Second moment of area (weak axis)
Wply_cm3	float	cm³	Plastic section modulus (strong axis)
Wplz_cm3	float	cm³	Plastic section modulus (weak axis)
iy_cm / iz_cm	float	cm	Radii of gyration
Ay_cm2 / Az_cm2	float	cm²	Shear areas
uf_width_mm	float	mm	Flange width
uf_thick_mm	float	mm	Flange thickness
web_thick_mm	float	mm	Web thickness
lf_thick_mm	float	mm	Lower flange thickness
material	string	—	Steel grade name
fy_MPa	float	MPa	Yield strength
E_GPa	float	GPa	Young's modulus
alpha_y / alpha_z	float	—	Buckling imperfection factors (EC3 Table 6.2)
alpha_lt	float	—	LT buckling imperfection factor (EC3 §6.3.2)
Lcr_y_mm	float	mm	Buckling length (strong axis)
Lcr_z_mm	float	mm	Buckling length (weak axis)
Lcr_lt_mm	float	mm	Lateral-torsional buckling length
lambda_y / lambda_z	float	—	Slenderness ratios
lambda_bar_y / lambda_bar_z	float	—	Non-dimensional slenderness (EC3 §6.3)
weight_kg	float	kg	Element steel weight
N_max_kN / N_min_kN	float	kN	Max/min axial force across all LCs
axial_by_lc	list[dict]	—	Axial force per load case
util_max	float	—	Peak EC3 utilization ratio (governing LC)
util_N	float	—	Axial force utilization at governing LC
util_Vy / util_Vz	float	—	Shear utilization at governing LC
util_My / util_Mz	float	—	Bending utilization at governing LC
is_ec3_ok	bool	—	True if util_max ≤ 1.0
govern_check	string	—	Governing EC3 check (N / My / Mz / Vy / Vz)
govern_lc	string	—	Name of governing load case combination

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Load Case Combinations (10 per frame)

All combinations follow EN 1990 Annex A1 ULS persistent/transient design situation with ψ₀ combination factors per EN 1991:

Name	Leading action
ULS_SnowLead	Snow dominant (wind as accompanying)
ULS_WindLead	Wind dominant (snow as accompanying)
+ 8 further combinations	Dead load, imposed, combinations thereof

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Data Generation Pipeline

Grasshopper / Rhinoceros 3D
  └── Parametric frame geometry (uniform random sampling)
  └── Karamba3D 3.1 FEM solver
        └── 10 ULS load case combinations (EN 1990 Annex A1)
        └── EC3 EN 1993-1-1:2005 cross-section + stability checks
        └── BeamView utilization component (max across all LCs)
        └── BeamDisplacements component (midspan deflection)
  └── GHPython 3 extractor (CPython 3.9, Rhino 8)
        └── frames.jsonl
        └── elements.jsonl

Solver: Karamba3D 3.1 (Clemens Preisinger, TU Vienna / Bollinger+Grohmann)
Design code: EC3 EN 1993-1-1:2005 with EN 1990 load combinations
Platform: Rhinoceros 8 / Grasshopper, Windows

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Known Limitations

• Column profiles limited to HEB only — HEA, UC, HD sections not included
• Rafter profiles limited to IPE only — welded, cellular, and tapered sections not included
• Wind pressure only — wind suction (uplift) load cases are not included; wind uplift on roof can govern rafter design in practice and is absent from this dataset
• 2D single-span frames only — no multi-bay, crane gantry, mezzanine, or 3D effects
• Connections not modelled — fully rigid frame assumption throughout
• No second-order (P-Δ) effects — first-order linear elastic analysis only
• 5 missing run_ids in SF-00001–SF-01000 sequence due to solver failures during batch generation

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Intended Use Cases

• Training ML regression models to predict util_max, frame_weight_kg, roof_mid_vert_defl_mm from geometric and load input parameters
• Training classification models to predict is_ec3_compliant
• Surrogate modelling for structural optimisation loops
• Benchmarking graph neural networks on 2D frame topology
• Research in AI-assisted structural design and automated EC3 checking
• Education — demonstrating EC3 design parameter sensitivity

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License

CC BY-NC 4.0 — free for research and non-commercial use with attribution.
For commercial licensing enquiries contact the author.

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Citation

@dataset{neiburgs_ec3_steel_frames_2025,
  title     = {EC3 Steel Portal Frame Structural Analysis Dataset},
  author    = {Neiburgs, Arturs},
  year      = {2025},
  publisher = {KOPAA},
  url       = {https://huggingface.co/datasets/kopaaParametric/ec3-steel-portal-frames},
  license   = {CC BY-NC 4.0},
  note      = {Generated with Karamba3D 3.1 / Grasshopper / Rhinoceros 8.
               995 frames, 3450 elements, EC3 EN 1993-1-1:2005.}
}

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Contact

Arturs Neiburgs
KOPAA
✉ arturs.neiburgs@kopaa.io
🔗 LinkedIn