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Tendon Property

Manages tendon properties and integrates relaxation models.

NODE GRID

Property highlighted in the box is defined through Relaxation defintion.

Constructor

Tendon.Property(name, type, matID: int, tdn_area, duct_dia, relaxation, ext_mom_mag=0, anch_slip_begin=0, anch_slip_end=0, bond_type: bool=True, id=0)

Creates a tendon property

Parameters

  • name (str): Name for the tendon property.
  • type (int): 1=Internal (Pre-tension) | 2=Internal (Post-tension) | 3=External.
  • matID (int): Steel Material ID.
  • tdn_area (float): Area of tendon.
  • duct_dia (float): Duct diameter.
  • relaxation: Relaxation definition.
  • ext_mom_mag (float, default=0): External moment magnifier.
  • anch_slip_begin (float, default=0): Anchorage slip at begin.
  • anch_slip_end (float, default=0): Anchorage slip at end.
  • bond_type (bool, default=True): Whether the tendon is bonded or unbonded.
  • id (int, default=0): Optional ID for tendon property.

Object Attributes

  • ID: Unique identifier (auto-generated)
  • NAME: Tendon name
  • TYPE: Tendon type (INTERNAL or EXTERNAL)
  • TENS: Tension type (PRE or POST)
  • MAT: Material ID
  • TDN_AREA: Tendon area
  • DUCT_DIA: Duct diameter
  • RELAX: Relaxation object
  • EXT_MOM_MAG: External moment magnitude
  • ANC_SLIP_B: Anchor slip at beginning
  • ANC_SLIP_E: Anchor slip at end
  • BOND_TYP: Bonded (True) or unbonded (False)

Class Attributes

Tendon.Property.properties -> List of all tendon properties defined.

Tendon.Property('TD_Prop',2,1,1700,100,Tendon.Relaxation.Null(1800,1500))
Tendon.Property('TD_Prop 2',1,1,1700,100,Tendon.Relaxation.CEBFIP_2010(0,2,1800,1500))

for prop in Tendon.Property.properties:
    print(f'NAME : {prop.NAME}  | TYPE: {prop.TYPE} {prop.TENS} TENSION ')

# Output:
# NAME : TD_Prop  | TYPE: INTERNAL POST TENSION
# NAME : TD_Prop 2  | TYPE: INTERNAL PRE TENSION

Methods

json

Returns a JSON representation of all Tendon Properties defined in python.

Tendon.Property('TD_Prop',2,1,1700,100,Tendon.Relaxation.Null(1800,1500))
print(Tendon.Property.json())

# Output:
# {'Assign': {1: {'NAME': 'TD_Prop', 'TYPE': 'INTERNAL', 'LT': 'POST', 'MATL': 1, 'AREA': 1700, 'D_AREA': 100, 'ASB': 0, 'ASE': 0, 'bBONDED': True, 'ALPHA': 0, 'RM': 0, 'RV': 0, 'US': 1800, 'YS': 1500, 'FF': 0, 'WF': 0, 'bRELAX': False}}}

create

Sends the current tendon properties defined to the Civil NX using a PUT request.
New properties are created and existing property(same ID) in Civil NX will be updated.

Tendon.Property('TD_Prop',2,1,1700,100,Tendon.Relaxation.Null(1800,1500)) # Assumes Material with ID=1
Tendon.Property.create()

get

Fetches tendon properties from the Civil NX and return the JSON representation.

print(Tendon.Property.get())
# Output:
# {'TDNT': {'1': {'NAME': 'TD_Prop', 'TYPE': 'INTERNAL', 'MATL': 1, 'AREA': 1700, 'D_AREA': 100, 'RM': 0, 'RV': 0, 'US': 1800, 'YS': 1500, 'LT': 'POST', 'ASB': 0, 'ASE': 0, 'bBONDED': True, 'ALPHA': 0, 'bRELAX': False, 'TDMFK': 0, 'FF': 0, 'WF': 0}}}

sync

Retrieves Tendon property data from the Civil NX and rebuilds the internal tendon property list.

Tendon.Property.sync()

delete

Deletes all tendon properties from both Python and Civil NX.

Tendon.Property.delete()

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Relaxation

The Relaxation class contains several code-specific inner classes to define tendon relaxation properties.
Each standard/code has its own constructor parameters and object attributes.

If no relaxation is required, Tendon.Relaxation.Null( ) should be used.

Null - No Relaxation

Null

Constructor

Tendon.Relaxation.Null( ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0)

Parameters

  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default is 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default is 0).

Object Attributes

  • CODE (str): 'No Relaxation'
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
CEB-FIP Code (2010)

CEBFIP_2010

Constructor

Tendon.Relaxation.CEBFIP_2010( rho, rel_class, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0, unint_ang_disp=0)

Parameters

  • rho (float): Relative relaxation loss after 1000 hours.
  • rel_class (int): Relaxation class (1: Slow, 2: Mean, 3: Rapid).
  • ult_st (float): Ultimate strength .
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default: 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default: 0).
  • unint_ang_disp (float, optional): Unintentional angular displacement (default: 0).

Object Attributes

  • CODE (str): 'CEB FIP-2010'
  • RHO (float): Relative relaxation value.
  • CLASS (int): Relaxation class.
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
  • UNINT_AD (float): Unintentional angular displacement.
CEB-FIP Code (1978)

CEBFIP_1978

Constructor

Tendon.Relaxation.CEBFIP_1978( rho, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0, unint_ang_disp=0)

Parameters

  • rho (float): Relative relaxation value.
  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default: 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default: 0).
  • unint_ang_disp (float, optional): Unintentional angular displacement (default: 0).

Object Attributes

  • CODE (str): 'CEB FIP-1978'
  • RHO (float): Relative relaxation value.
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
  • UNINT_AD (float): Unintentional angular displacement.
CEB-FIP Code (1990)

CEBFIP_1990

Constructor

Tendon.Relaxation.CEBFIP_1990( rho, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0, unint_ang_disp=0)

Parameters

  • rho (float): Relative relaxation value.
  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default: 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default: 0).
  • unint_ang_disp (float, optional): Unintentional angular displacement (default: 0).

Object Attributes

  • CODE (str): 'CEB FIP-1990'
  • RHO (float): Relative relaxation value.
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
  • UNINT_AD (float): Unintentional angular displacement.
European

European

Constructor

Tendon.Relaxation.European( rel_class, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0, unint_ang_disp=0)

Parameters

  • rel_class (int): Relaxation class (1: Ordinary, 2: Low, 3: HotRolled).
  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default: 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default: 0).
  • unint_ang_disp (float, optional): Unintentional angular displacement (default: 0).

Object Attributes

  • CODE (str): 'European'
  • CLASS (int): Relaxation class.
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
  • UNINT_AD (float): Unintentional angular displacement.
IRC 18 - 2000

IRC_18

Constructor

Tendon.Relaxation.IRC_18( factor, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0)

Parameters

  • factor (float): Relaxation factor.
  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default: 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default: 0).

Object Attributes

  • CODE (str): 'IRC:18-2000'
  • FACTOR (float): Relaxation factor.
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
IRC 112 - 2020

IRC_112

Constructor

Tendon.Relaxation.IRC_112( factor, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0)

Parameters

  • factor (float): Relaxation factor (code-specific parameter).
  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default is 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default is 0).

Object Attributes

  • CODE (str): 'IRC:112-2011'
  • FACTOR (float): Relaxation factor.
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.
Magura et al. 1964

Magura

Constructor

Tendon.Relaxation.Magura( factor, ult_st, yield_st, curv_fric_fac=0, wob_fric_fac=0)

Parameters

  • factor (int): Relaxation factor; must be either 10 or 45. If not, defaults to 45.
  • ult_st (float): Ultimate strength.
  • yield_st (float): Yield strength.
  • curv_fric_fac (float, optional): Curvature friction factor (default is 0).
  • wob_fric_fac (float, optional): Wobble friction factor (default is 0).

Object Attributes

  • CODE (str): 'Magura'
  • FACTOR (int): Relaxation factor (either 10 or 45).
  • ULT_ST (float): Ultimate strength.
  • YIELD_ST (float): Yield strength.
  • CURV_FF (float): Curvature friction factor.
  • WOBBLE_FF (float): Wobble friction factor.

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Examples

from midas_civil import *

Material.STEEL('TD_steel','IS(S)','E450')
Tendon.Property('TD_Prop',2,1,1700,100,Tendon.Relaxation.Null(1800,1500))
Tendon.Property('TD_Prop 2',1,1,1700,100,Tendon.Relaxation.CEBFIP_2010(0,2,1800,1500))

Model.create()