TY - GEN
T1 - Experimental and numerical investigation of novel crack stopper concepts for lightweight foam cored sandwich structures
AU - Wang, W.
AU - Martakos, G.
AU - Dulieu-Barton, J. M.
AU - Thomsen, O. T.
PY - 2017
Y1 - 2017
N2 - Three novel crack stopper designs for foam cored composite sandwich structures have been investigated with respect to their ability to deflect and arrest propagating face debond cracks. One of the new crack stoppers was similar to a previously developed design, whereas the two others were modified with layers of glass fibre fabric extending from the peel stopper tip into the face sheet, or into the face sheet/core interface. The novel designs were investigated under mode I dominated crack propagation conditions. Both quasi-static and fatigue loading scenarios were investigated. The mechanisms controlling crack propagation were studied using Thermoelastic Stress analysis (TSA) and Finite Element (FE) analysis. The TSA revealed significant new information about the local stress fields in the vicinity of the crack stopper tip as well as the fracture process zone. The first configuration in most cases was able to deflect debond cracks, albeit not in all cases, whereas it was incapable of achieving crack arrest. The two other designs performed better in that they consistently demonstrated the ability to deflect propagating cracks. Only the second design could arrest the cracks consistently as well. Detailed numerical fracture mechanics analyses confirmed and explained the experimental observations.
AB - Three novel crack stopper designs for foam cored composite sandwich structures have been investigated with respect to their ability to deflect and arrest propagating face debond cracks. One of the new crack stoppers was similar to a previously developed design, whereas the two others were modified with layers of glass fibre fabric extending from the peel stopper tip into the face sheet, or into the face sheet/core interface. The novel designs were investigated under mode I dominated crack propagation conditions. Both quasi-static and fatigue loading scenarios were investigated. The mechanisms controlling crack propagation were studied using Thermoelastic Stress analysis (TSA) and Finite Element (FE) analysis. The TSA revealed significant new information about the local stress fields in the vicinity of the crack stopper tip as well as the fracture process zone. The first configuration in most cases was able to deflect debond cracks, albeit not in all cases, whereas it was incapable of achieving crack arrest. The two other designs performed better in that they consistently demonstrated the ability to deflect propagating cracks. Only the second design could arrest the cracks consistently as well. Detailed numerical fracture mechanics analyses confirmed and explained the experimental observations.
KW - Damage tolerance
KW - Foam cored composite sandwich structures
KW - Fracture modelling
KW - Peel stoppers
KW - Thermoelastic stress analysis
UR - http://www.scopus.com/inward/record.url?scp=84989345376&partnerID=8YFLogxK
U2 - 10.1007/978-3-319-42195-7_15
DO - 10.1007/978-3-319-42195-7_15
M3 - Article in proceeding
AN - SCOPUS:84989345376
SN - 9783319421940
VL - 8
T3 - Conference Proceedings of the Society for Experimental Mechanics Series
SP - 107
EP - 110
BT - Fracture, Fatigue, Failure and Damage Evolution - Proceedings of the 2016 Annual Conference on Experimental and Applied Mechanics
PB - Springer
T2 - Annual Conference and Exposition on Experimental and Applied Mechanics, 2016
Y2 - 6 June 2016 through 9 June 2016
ER -