Effect of axial shear and transverse tension on early failure events in unidirectional polymer matrix composites

Effect of multiaxiality, stacking sequence and number of off-axis layers on the mechanical response and damage sequence of carbon/epoxy composite laminates under static loading

“…However this approach, based only on calculation of stresses while neglecting the physical presence of damage, lacks in reliability since the stress state in a composite lamina can change from point to point, therefore unique values of stress components in a layer cannot be assumed [6]- [9]. Moreover, whereas the applicability of these criteria can be accepted for more common lay-ups, like for example cross-ply laminates, it is questioned when off-axis layers are inserted in the laminate [10]- [13], leading to the development of biaxial/multiaxial stress states. According to the World-Wide Failure Exercise (WWFE) [14], there is a high need for dedicated experimental campaigns focusing on the influence of multiaxial stress states on the mechanical response of composites.…”

Hybrid multiscale procedure for damage in notched unidirectional composite monitored by thermography

“…where, the fiber tensile and compressive strengths, S f t and S f c , the matrix shear strength, S m s , the matrix critical dilatation energy density u c v and the interface strength, S i . The factors 0.92 in Equation ( 10) and 0.8 in Equation (11) are calibrated based in fiber in situ strength reduction and fiber misalignment considering a set of 88 experimental data. [34] Additionally,…”

“…Despite the recent advances concerning damage modeling in composite materials, [ 8,9 ] the damage onset, a matter of practical importance, is still receiving modest attention, due to the experimental measurement difficulties. [ 10,11 ] Some experimental efforts have been carried out to improve damage measurements: Iarve et al [ 12 ] and Mollenhauer et al, [ 13 ] which employed Moiré interferometric technique; Llobet et al [ 14 ] that used X‐ray inspections; Ni et al, [ 15 ] which studied synchrotron computed tomography application; and Eder et al [ 16 ] that presented thermal image results for fatigue damage.…”

Comprehensive inter-fibre failure analysis and failure criteria comparison for composite materials using micromechanical modelling under biaxial loading

“…fibres, matrix and fibre/matrix interface) to infer the mechanical behaviour of composites. 17 Recently, micromechanics-based modelling has been successfully applied to investigate the mechanical behaviour of composites and assess the abovementioned failure criteria and/or models under different biaxial loading conditions, such as combined transverse and out-of-plane shear, 1,18 combined transverse and in-plane shear, 1,[19][20][21][22][23][24] combined transverse compression and axial tension, 25 combined longitudinal tension and in-plane shear 1 and triaxial loadings. 26 Sun et al 1 conducted a computational failure analysis of composites under three sets of biaxial loading conditions and assessed several widely used failure criteria.…”