TY - JOUR

T1 - Delamination growth in composite laminates of variable stiffness

AU - Yazdani, Saleh

AU - Rust, Wilhelm J.H.

AU - Wriggers, Peter

PY - 2016/4/11

Y1 - 2016/4/11

N2 - The production of new composite laminates with variable stiffness within the surface of plies was enabled by tow-placement machines. Because of the variation of stiffness, these materials are called variable stiffness composite laminates (VSCL). Recently, many attempts were made to investigate their structural behaviour. In this contribution, a first-order shear deformation theory is selected to model the multilayered composite laminates. The adopted theory is enhanced by the extended finite element method (XFEM) to describe discontinuities at element level of any interface of interest. To predict the location of the delamination onset, a traction–separation law is developed that is consistent with the XFEM topology. An exponential softening behaviour is implemented within the interface to model the delamination growth in a mixed-mode direction. In order to solve the non-linear equations of the delamination propagation, an arc-length method is applied. The effect of the curvilinear fibre orientation on the location of the delamination onset is investigated. Subsequently, the structural response of the laminates is computed. According to the simplicity of the new approach using the XFEM; and based on the computational cost for calculating the stiffness of VSCL, the method is able to determine structural response of VSCL with less computational effort.

AB - The production of new composite laminates with variable stiffness within the surface of plies was enabled by tow-placement machines. Because of the variation of stiffness, these materials are called variable stiffness composite laminates (VSCL). Recently, many attempts were made to investigate their structural behaviour. In this contribution, a first-order shear deformation theory is selected to model the multilayered composite laminates. The adopted theory is enhanced by the extended finite element method (XFEM) to describe discontinuities at element level of any interface of interest. To predict the location of the delamination onset, a traction–separation law is developed that is consistent with the XFEM topology. An exponential softening behaviour is implemented within the interface to model the delamination growth in a mixed-mode direction. In order to solve the non-linear equations of the delamination propagation, an arc-length method is applied. The effect of the curvilinear fibre orientation on the location of the delamination onset is investigated. Subsequently, the structural response of the laminates is computed. According to the simplicity of the new approach using the XFEM; and based on the computational cost for calculating the stiffness of VSCL, the method is able to determine structural response of VSCL with less computational effort.

KW - cohesive

KW - delamination

KW - VSCL

KW - XFEM

UR - http://www.scopus.com/inward/record.url?scp=84965117244&partnerID=8YFLogxK

U2 - 10.1002/nme.5264

DO - 10.1002/nme.5264

M3 - Article

AN - SCOPUS:84965117244

VL - 108

SP - 1406

EP - 1424

JO - International Journal for Numerical Methods in Engineering

JF - International Journal for Numerical Methods in Engineering

SN - 0029-5981

IS - 11

ER -