Codes

I am glad to share the developed computational codes during our research. Please cite the corresponding paper(s) if you use any of these codes. Feel free to contact me if you have any questions.

1. Phase field fracture model

A computational framework to explore the effect of microstructure and constituent properties upon the fracture toughness of fibre-reinforced polymer composites is presented.  A phase field fracture method and a cohesive zone model are coupled to capture microscopic matrix cracking and fibre-matrix debonding. This model is possible to accurately capture the crack path, interface debonding and load versus displacement response. The sensitivity of the crack growth resistance curve (R-curve) to the matrix fracture toughness and the fibre-matrix interface properties is determined. The influence of porosity upon the R-curve of fibre-reinforced composites is also explored, revealing a higher crack growth resistance with increasing void volume fraction. These results shed light into microscopic fracture mechanisms and set the basis for efficient design of high fracture toughness composites.

Click the link to download: Codes link or Github repository. Please contact me if you have any questions (wei.tan@qmul.ac.uk) or Dr. Emilio Martinez-Paneda (e.martinez-paneda@imperial.ac.uk)

Reference:

[1] W. Tan, B.G. Falzon, L.N.S. Chiu, M. Price, Predicting low velocity impact damage and Compression-After-Impact (CAI) behaviour of composite laminates, Compos. Part A 71 (2015) 212-226.

[2] W. Tan, and E. Martinez-Paneda, Phase field predictions of microscopic fracture and R-curve behaviour of fibre-reinforced composites. Compos. Sci. Technol. 2021.

2. Crystal plasticity model for composite laminates

By analogy, we developed a micromechanical model to capture the matrix shearing and fibre rotation of CFRP under finite strain and different strain rates, inspired by the crystal plasticity theory. Strain rate dependency of the shear modulus and yield strength of matrix is modelled through scaling functions [3]. We then validate the predictive capabilities of this micromechanical model against the measured stress-strain responses of unidirectional (UD) and cross-ply composite laminates.  

Click the link to download: Codes link. Please contact me if you are interested (wei.tan@qmul.ac.uk) or Dr Liu. B (bl377@eng.cam.ac.uk).

References:

[3] Tan, W. and Liu, B., 2020. A physically-based constitutive model for the shear-dominated response and strain rate effect of Carbon Fibre Reinforced composites. Composites Part B: Engineering, p.108032.

3. Continuum damage model

Throughout the years, we have developed a continuum damage model [4] to model the nonlinear behaviour of fibre-reinforced composite, considering fibre and matrix damage. This model was used to predict both low-velocity impact damage and CAI strength of composite laminates, has been developed and implemented as a user material subroutine in the commercial finite element package, ABAQUS/Explicit. 

Click the link to download: Codes link. Please contact me if you have any questions (wei.tan@qmul.ac.uk) or Prof. Brian Falzon (brian.falzon@rmit.edu.au)

Reference:

[4] W. Tan, B.G. Falzon, L.N.S. Chiu, M. Price, Predicting low velocity impact damage and Compression-After-Impact (CAI) behaviour of composite laminates, Compos. Part A 71 (2015) 212-226. (JCR Q1, IF:6.28, Citations: 280+).

4. Cohesive zone model

Cohesive elements are commonly used in modelling adhesives, bonded interfaces, composite laminates. The constitutive response of these elements usually assume a traction-separation law of the interface. Just like assuming the cohesive element as a linear-elastic spring. It will be able to pick up loading in mode I (open) and mode II (shear). Damage initiates when the assumed criteria is reached (e.g. Maximum stress, Quadratic nominal stress criterion). The damage evolution will be governed by a defined fracture toughness value (e.g. critical energy release rate Gc).

Click the link to download: Code link: Please contact me for more questions (wei.tan@qmul.ac.uk)

Reference:

[2] W. Tan, and E. Martinez-Paneda, Phase field predictions of microscopic fracture and R-curve behaviour of fibre-reinforced composites. Compos. Sci. Technol. 2021.