A fatigue failure criterion for predicting the fatigue life of notched orthotropic fiber reinforced plasties (FRP) plates based on the concept of stress field intensity (SFI) near the notch root is subjected to furt...A fatigue failure criterion for predicting the fatigue life of notched orthotropic fiber reinforced plasties (FRP) plates based on the concept of stress field intensity (SFI) near the notch root is subjected to further experiments. The investigation is accomplished by obtaining experimental data on the notched specimens of glass fiber reinforced plastics (GFRP) with edged notches under tension tension cyclic loading. The process of initiation and growth of fatigue damage near the notch root is measured by means of the optic system with a computer controlled display (CCD) camera. The experimental results show that the number of loading cycles required to initiate fatigue damage is governed by the stress field intensity.展开更多
Structural impact tests were first presented to cover typical fibre metal laminates (FMLs) subjected a low velocity projectile impact,which produced the corresponding load-displacement traces and deformation/failure m...Structural impact tests were first presented to cover typical fibre metal laminates (FMLs) subjected a low velocity projectile impact,which produced the corresponding load-displacement traces and deformation/failure modes for the validation of numerical models.Finite element (FE) models were then developed to simulate the impact behaviour of FMLs tested.The aluminium (alloy grade 2024-0) layer was modelled as an isotropic elasto-plastic material up to the on-set of post failure stage,followed by shear failure and tensile failure to simulate its failure mechanisms.The glass fibre laminate (woven glass-fibre reinforced composite) layer was modelled as an orthotropic material up to its on-set of damage,followed by damage initiation and evolution using the Hashin criterion.The damage initiation was controlled by failure tensile and compressive stresses within the lamina plane which were primarily determined by tests.The damage evolution was controlled by tensile/compressive fracture energies combined with both fibre and matrix.The FE models developed for the 2/1,3/2 and 4/3 FMLs plates made with 4-ply and 8-ply glass fibre laminate cores were validated against the corresponding experimental results.Good correlation was obtained in terms of load-displacement traces,deformation and failure modes.The validated models were ready to be used to undertake parametric studies to cover FMLs plates made with various stack sequences and composite cores.展开更多
文摘A fatigue failure criterion for predicting the fatigue life of notched orthotropic fiber reinforced plasties (FRP) plates based on the concept of stress field intensity (SFI) near the notch root is subjected to further experiments. The investigation is accomplished by obtaining experimental data on the notched specimens of glass fiber reinforced plastics (GFRP) with edged notches under tension tension cyclic loading. The process of initiation and growth of fatigue damage near the notch root is measured by means of the optic system with a computer controlled display (CCD) camera. The experimental results show that the number of loading cycles required to initiate fatigue damage is governed by the stress field intensity.
基金supported by a PhD studentship of the University of Liverpoolsupported by the Engineering and Physical Sciences Research Council (EPSRC)
文摘Structural impact tests were first presented to cover typical fibre metal laminates (FMLs) subjected a low velocity projectile impact,which produced the corresponding load-displacement traces and deformation/failure modes for the validation of numerical models.Finite element (FE) models were then developed to simulate the impact behaviour of FMLs tested.The aluminium (alloy grade 2024-0) layer was modelled as an isotropic elasto-plastic material up to the on-set of post failure stage,followed by shear failure and tensile failure to simulate its failure mechanisms.The glass fibre laminate (woven glass-fibre reinforced composite) layer was modelled as an orthotropic material up to its on-set of damage,followed by damage initiation and evolution using the Hashin criterion.The damage initiation was controlled by failure tensile and compressive stresses within the lamina plane which were primarily determined by tests.The damage evolution was controlled by tensile/compressive fracture energies combined with both fibre and matrix.The FE models developed for the 2/1,3/2 and 4/3 FMLs plates made with 4-ply and 8-ply glass fibre laminate cores were validated against the corresponding experimental results.Good correlation was obtained in terms of load-displacement traces,deformation and failure modes.The validated models were ready to be used to undertake parametric studies to cover FMLs plates made with various stack sequences and composite cores.