norma-ntc 0.3.0

Python library for structural verification according to NTC 2018 (Italian Building Code)

pyntc

Python library for structural verification according to NTC 2018 (Italian Building Code, D.M. 17/01/2018).

Disclaimer: This library does not replace the professional judgement of the structural engineer. Final verification is the responsibility of the designer.

Installation

pip install norma-ntc

Quick start

from pyntc.actions.loads import unit_weight, variable_load, partition_equivalent_load
from pyntc.actions.wind import (
    wind_base_velocity,
    wind_reference_velocity,
    wind_kinetic_pressure,
    wind_exposure_coefficient,
    wind_pressure,
)

# --- Carichi (NTC18 §3.1) ---
gamma = unit_weight("calcestruzzo_armato")          # 25.0 kN/m³
qk, Qk, Hk = variable_load("A")                    # (2.0, 2.0, 1.0)
g2 = partition_equivalent_load(1.5)                  # 0.80 kN/m²

# --- Vento (NTC18 §3.3) ---
v_b = wind_base_velocity(zone=3, altitude=600)       # 29.00 m/s
v_r = wind_reference_velocity(3, 600, 50)            # 29.02 m/s
q_b = wind_kinetic_pressure(v_r)                     # 0.526 kN/m²
c_e = wind_exposure_coefficient(z=15, exposure_category=3)  # 2.407
p   = wind_pressure(q_b, c_e, c_p=0.8)              # 1.014 kN/m²

Modules

Actions (NTC18 Cap. 2-3) — input to the solver

Module	Section	Description
actions.loads	§3.1	Dead loads, partitions, variable loads, reduction factors
actions.wind	§3.3	Base velocity, return coefficient, kinetic pressure, exposure, wind pressure
actions.snow	§3.4	Ground load, shape/exposure coefficients, roof load
actions.seismic	§3.2	Return period, damping, soil/topographic amplification, elastic response spectrum
actions.temperature	§3.5	Temperature extremes, solar increment, uniform variation
actions.fire	§3.6	Standard/hydrocarbon/external curves, design load, explosion, impact
actions.combinations	§2.5.3	ψ coefficients, γ factors, SLU/SLE/seismic/exceptional combinations, seismic masses

Checks (NTC18 Cap. 4-8) — verification of solver output

Module	Section	Description
checks.concrete	§4.1	R.C. design strengths, strain limits, shear/torsion resistance, biaxial bending
checks.steel	§4.2	Steel grade properties, section resistance (N/M/V), buckling, bolts, welds
checks.composite	§4.3	Composite steel-concrete: effective width, studs, columns, beams
checks.timber	§4.4	Timber: k_mod/k_def, design strength, bending/shear/torsion, beam/column stability
checks.masonry	§4.5	Masonry: partial factors, slenderness, eccentricity, simplified check
checks.bridges	Cap. 5	Bridge load schemes (road/rail), dynamic coefficients, braking/centrifugal forces
checks.geotechnical	Cap. 6	Geotechnical: partial factors, piles, anchors, retaining walls, embankments
checks.seismic_design	Cap. 7	Seismic design: behaviour factor, modal combination, capacity design
checks.existing_buildings	Cap. 8	Existing buildings: confidence factors, safety ratios, adequacy checks

Design principles

• External solver: pyntc produces input (actions) and verifies output (checks) — it is NOT a FEM solver
• Traceability: every public function is decorated with @ntc_ref(article=..., table=..., formula=...) linking back to NTC18
• SI units: all quantities in SI, documented in docstrings between []
• Minimal dependencies: only numpy (core) and scipy (optional)

Development

pip install -e ".[dev]"
pytest -v
pytest --cov=pyntc

License

MIT