Model

class czmtestkit.py_modules.Model

Bases: object

Parent class for analytical models of standardized tests described in appendix B of the master thesis [1].

References:

Mudunuru, N. (2022, March 30). Finite Element Model For Interfaces In Compatibilized Polymer Blends. TU Delft Education Repositories. Retrieved on April 21, 2022, from http://resolver.tudelft.nl/uuid:88140513-120d-4a34-b893-b84908fe2373

Metadata

Environment

Abaqus/CAE

Version

v1.0.0

Date

2022-01-18

Authors

Nanditha Mudunuru

Contribution: v1.0.0

Email: nanditha.mudunuru@gmail.com

Methods Summary

`rCurve`([u, P, data])	Find the effective fracture resistance (G) and instantaneous crack length, given the reaction force corresponding to open displacements.
`reactionForce`([u, data])	Find the reaction force corresponding to open displacements, given the critical fracture toughness ( \(G_C\) ).
`setup`([data])	Setup class attributes corresponding to specimen geometry and properties.

Methods Documentation

rCurve(u=None, P=None, data=None)

Find the effective fracture resistance (G) and instantaneous crack length, given the reaction force corresponding to open displacements.

Parameters

P (float or list): reaction force.

u (float or list): opening displacement.

data (dict) Optional : Specimen dimensions and properties. See Model.setup() for required key-value pairs in addition to the following:

‘Displacement’

list of opening displacements.

‘Reaction Force’

list of reaction forces.

Note

If the setup() method of Model or one of its child classes has already been executed, pass the displacement and reaction force inputs to rCurve() method using the u and P arguments. If not, the input dictionary from Model.setup() must be passed along with the additional key-value pairs using the data argument. Either data or the P, u arguments are required, not both.

Warning

Can only be used when a child class with methods setup() and resistance() are defined. For example, see czmtestkit.py_modules.ADCB, czmtestkit.py_modules.ASLB and czmtestkit.py_modules.ENF

reactionForce(u=None, data=None)

Find the reaction force corresponding to open displacements, given the critical fracture toughness ( \(G_C\) ).

Parameters

u (float or list): opening displacement.

data (dict) Optional : Specimen dimensions and properties. See Model.setup() for required key-value pairs in addition to the following:

‘Displacement’

list of opening displacements.

‘gT’

Fracture toughness.

Note

If the setup() method of Model or one of its child classes has already been executed, pass the displacement to reactionForce() method using the u argument. If not, the input dictionary from Model.setup() must be passed along with the additional key-value pairs using the data argument. Either the data or the u arguments are required, not both.

Warning

Can only be used when a child class with methods setup(), crackLength() and compliance() are defined. For example, see czmtestkit.py_modules.ADCB, czmtestkit.py_modules.ASLB and czmtestkit.py_modules.ENF

setup(data=None)

Setup class attributes corresponding to specimen geometry and properties.

Parameters

data (dict) Optional : Specimen dimensions and properties.

Only necessary if setup() method of a child class has not been previously executed.
‘JobID’

Name of the job.

‘Length’

Length of the specimen \(2L\).

‘Width’

Width of the specimen \(B\).

‘tTop’

Thickness of the top adherand/ply \(h_u\).

‘tBot’

Thickness of the bottom adherand/ply \(h_l\).

‘tCz’

Thickness of the cohesive zone \(t\).

‘Crack’

Crack length \(a_0\).

‘E’ or ‘ETop’
Tuple of engineering constants for the elastic behaviour of the top adherand/ply.
(E1,E2,E3,ν12,ν13,ν23,G12,G13,G23)

Warning

The input parameters should be consistent in their units of measurement. Following are some commonly used groups of units in engineering:

Table 5 Consistent set of units [1].
MASS	LENGTH	TIME	FORCE	STRESS	ENERGY
kg	m	s	N	Pa	J
kg	mm	ms	kN	GPa	kN-mm
g	mm	ms	N	MPa	N-mm

References:

LS-Dyna. (n.d.). Consistent units. Retrieved April 21, 2022, from https://www.dynasupport.com/howtos/general/consistent-units