simdesign.rcmrf.bdim.eu_cdh.column

This module provides the column class implementation for the eu_cdh design class in the BDIM layer.

class simdesign.rcmrf.bdim.eu_cdh.column.Column(line, section, gamma_rc)[source]

Bases: ColumnBase

Column implementation for design class eu_cdh.

This class extends ColumnBase by narrowing the attribute types and overriding design methods per Eurocodes 2 and 8.

Parameters:

  • line (Line)

  • section (Literal[1, 2])

  • gamma_rc (float)

steel

Steel material assigned to the column.

Type:

Steel

concrete

Concrete material assigned to the column.

Type:

Concrete

See also

ColumnBase

Base class defining the core behaviour and configuration.

References

Comité Européen de Normalisation, CEN (2004). Eurocode 2: Design of Concrete Structures — Part 1-1: General Rules and Rules for Buildings. European Committee for Standardization, Brussels, Belgium.

Comité Européen de Normalisation, CEN (2004). Eurocode 8: Design of Structures for Earthquake Resistance — Part 1: General Rules, Seismic Actions and Rules for Buildings. European Committee for Standardization, Brussels, Belgium.

d’Arga e Lima, J., Monteiro, V., Mun, M. (2005). Betão armado: esforços normais e de flexão: REBAP-83. Laboratório Nacional de Engenharia Civil, Lisboa.

property Ix_eff: float
Returns:

Effective column moment of inertia around x-axis.

Return type:

float

property Iy_eff: float
Returns:

Effective column moment of inertia around y-axis.

Return type:

float

property rhol_max: float
Returns:

Maximum longitudinal reinforcement ratio.

Return type:

float

property rhol_min: float
Returns:

Minimum longitudinal reinforcement ratio.

Return type:

float

property rhoh_min: float
Returns:

Minimum transverse reinforcement ratio.

Return type:

float

Notes

The equation used herein is originally defined for beams. We keep using it for columns just to ensure safety.

predesign_section_dimensions()[source]

Make an initial guess for column section dimensions.

Notes

This method overrides ColumnBase.predesign_section_dimensions with the following changes:

  • Minimum cross section area is calculated based on axial load ratio limit from EC8.

Return type:

None

verify_section_adequacy()[source]

Verify the adequacy of section dimensions for design forces.

Notes

  • In accordance with EN 1992-1-1:2004 5.4.3.2.1(2) biaxial bending is taken into account by decreasing the uniaxial moment of resistance by 30%.

Return type:

None

compute_required_longitudinal_reinforcement()[source]

Compute the required longitudinal reinforcement for design forces.

Notes

  • In accordance with EN 1992-1-1:2004 5.4.3.2.1(2) biaxial bending is taken into account by decreasing the uniaxial moment of resistance by 30%.

Return type:

None

compute_required_transverse_reinforcement()[source]

Compute the required transverse reinforcement for design forces.

Return type:

None

check_local_ductility_requirement(combo_grav_factors, q0=3.9, T1=None, Tc=None)[source]

Checks the confinement of the critical region at the base of the column against the local ductility requirement of EN 1998-1:2004, 5.4.3.2.2(8), Eq. 5.15:

alpha omega_wd >= 30 mu_phi nu_d eps_syd bc / b0 - 0.035

Parameters:

  • combo_grav_factors (List[Dict[Literal['G', 'Q'], float]]) – Gravity load factors of the seismic load combinations, e.g., from the _get_unique_seism_combo_grav_factors method of the building. The largest normalised axial force nu_d governs.

  • q0 (float, optional) – Basic value of the behaviour factor. By default 3.9, i.e., 3.0 alpha_u / alpha_1 with alpha_u / alpha_1 = 1.3 for a multi-storey, multi-bay frame of DCM (EN 1998-1:2004, 5.2.2.2).

  • T1 (float | None, optional) – Fundamental period of the building. If None (or Tc is None), T1 >= Tc is assumed. By default None.

  • Tc (float | None, optional) – Corner period of the constant spectral acceleration branch. By default None.

Returns:

  • ok (bool) – True if the requirement is satisfied.

  • alpha_omega_wd (float) – Provided value alpha omega_wd.

  • required (float) – Required value 30 mu_phi nu_d eps_syd bc / b0 - 0.035.

Return type:

Tuple[bool, float, float]

Notes

  • The check applies to the critical regions at the base of primary seismic columns; the caller selects these columns. The column attributes are not changed.

  • Curvature ductility factor (EN 1998-1:2004, 5.2.3.4(3), Eq. 5.4): mu_phi = 2 q0 - 1 if T1 >= Tc, otherwise mu_phi = 1 + 2 (q0 - 1) Tc / T1. The periods are not estimated by the design; without them T1 >= Tc is assumed, which gives the smaller value for short-period buildings.

  • omega_wd is the mechanical volumetric ratio of the hoops within the confined core, (hoop volume / core volume) fyd / fcd. The core dimensions b0 and h0 are measured to the centreline of the hoops.

  • Confinement effectiveness factor alpha = alpha_n alpha_s (Eqs. 5.16a and 5.16b), with the distances bi between the centres of consecutive perimeter bars from the bar layout, i.e., all perimeter bars are assumed to be engaged by a hoop corner or a cross-tie.

  • bc / b0 is taken for the direction with the larger ratio.

References

CEN (2004) Eurocode 8: Design of structures for earthquake resistance - Part 1: General rules, seismic actions and rules for buildings. EN 1998-1:2004. Brussels, Belgium.