NOTE: This CDM routine is working for single element models (i.e. it passes single element verification tests), but is highly unstable for multi-element models. If you spot a bug or any other inconsistency let me know (contact details below).

3D Continuum Damage Mechanics VUMAT for Composite Materials

Explicit material subroutine (VUMAT) implementing a continuum damage mechanics (CDM) model for composite materials in Abaqus (in fixed format Fortran 77).

Summary

The continuum damage mechanics model implemented in this subroutine is based on the work of several authors. Failure stresses are calculated according to the three-dimensional failure criteria developed by Catalanotti et al. [1]. Damage evolution is adapted from the work of Maimi et al. [2][3] and Tan et al. [4][5].

The verification directory contains the input files required to run single-element simulations that verify the model correctly predicts the failure stress and energy dissipation for different types of loading.

The examples directory contains the input files required to run a number of simple simulations illustrating the flexibility of the model.

Usage

To run a simulation using subroutines your Abaqus installation must be linked with a Fortran compiler and compatible Visual Studio installation, see:

The model requires the following material properties to be defined in the simulation input (.inp) file:
E₁₁ = elastic modulus in the fiber direction
E₂₂= elastic modulus transverse direction (in-plane)
E₃₃ = elastic modulus transverse direction (out-of-plane)
ν₁₂ = Poisson's ratio 12 direction
ν₁₃ = Poisson's ratio 13 direction
ν₂₃ = Poisson's ratio 23 direction
G₁₂ = shear modulus 12 direction
G₁₃ = shear modulus 13 direction
G₂₃ = shear modulus 23 direction
X_T = tensile strength fiber direction
X_C = compressive strength fiber direction
Y_T^is = in-situ tensile strength transverse direction
Y_C^is = in-situ compressive strength transverse direction
S_L^is = in-situ longitudinal shear strength
S_T^is = in-situ transverse shear strength
η_L = shear friction coefficient longitudinal direction
α₀ = failure plane angle pure transverse compression
G₁₊ = tensile fracture toughness fiber direction
G_1- = compressive fracture toughness fiber direction
G₂₊ = tensile fracture toughness transverse direction
G₆ = shear fracture toughness

List of Fortran source code

composite_cdm.for : Implementation of CDM model in fixed format Fortran 77 (compatible with all Abaqus installations)

List of Verification Models

Tension_11 : Pure tension in fiber direction
Tension_22 : Pure tension in transverse direction
Compression_11 : Pure compression in fiber direction
Shear_12 : Shear in the 12 direction
Shear_23 : Shear in the 23 direction

List of Example Models

placeholder : TBD

Rutger Kok
PhD Candidate
email : rutger.kok@ed.ac.uk

Institute for Infrastructure and Environment
University of Edinburgh
Thomas Bayes Road, King's Buildings, Edinburgh EH9 3FG
United Kingdom

[1] G. Catalanotti, P.P. Camanho, A.T. Marques
Three-dimensional failure criteria for fiber-reinforced laminates
Composite Structures 95 (2013) 63–79
http://dx.doi.org/10.1016/j.compstruct.2012.07.016

[2] P. Maimi, P.P. Camanho, J.A. Mayugo, C.G. Davila
A continuum damage model for composite laminates: Part I – Constitutive model
Mechanics of Materials 39 (2007) 897–908
http://dx.doi.org/10.1016/j.mechmat.2007.03.005

[3] P. Maimi, P.P. Camanho, J.A. Mayugo, C.G. Davila
A continuum damage model for composite laminates: Part II – Computational implementation and validation
Mechanics of Materials 39 (2007) 909–919
http://dx.doi.org/10.1016/j.mechmat.2007.03.006

[4] W. Tan, B. G. Falzon, L. N. S. Chiu, and M. Price
Predicting low velocity impact damage and Compression-After-Impact (CAI) behaviour of composite laminates
Composites Part A 71 (2015) 212–226.
http://doi.org/10.1016/j.compositesa.2015.01.025