Fig. 1.
Test specimens
Fig. 2.
Specimen in the Z100 Zwick electromechanical testing machine at DIC system
Fig. 3.
Numerical model (with boundary conditions)
Fig. 4.
Force versus shortening: a) specimen A-1, b) specimen B-1, c) specimen C-1
Fig. 5.
Buckling modes: a) specimen A (FEM), b) specimen A (EXP), c) specimen B (FEM), d) specimen B (EXP), e) specimen C (FEM), c) specimen C (EXP)
Tab. 1.
Buckling force values
| 1 (EXP) | 2 (EXP) | 3 (EXP) | EXPavg | EXPSD | FEM | FEM/EXPavg | |
|---|---|---|---|---|---|---|---|
| A | 19,169 N | 18,512 N | 19,002 N | 18,894 N | 279 N | 20,671 N | 1.09 |
| B | 18,544 N | 18,892 N | 18,771 N | 18,736 N | 144 N | 19,556 N | 1.04 |
| C | 13,818 N | 13,352 N | 13,284 N | 13,485 N | 237 N | 14,037 N | 1.04 |
Fig. 6.
Force versus shortening at the damage initiation stage: a) specimen B-1, b) specimen B-2, c) specimen B-3
Fig. 7.
Graphical representation of damage initiation for FEA simulations
Tab. 2.
Damage initiation force values
| 1 (EXP) | 2 (EXP) | 3 (EXP) | EXPavg | EXPSD | FEM | FEM/EXPavg | |
|---|---|---|---|---|---|---|---|
| A | 20,234 N | 23,557 N | 21,042 N | 21,611 N | 1,415 N | 24,694 N | 1.14 |
| B | 27,537 N | 26,916 N | 27,615 N | 27,356 N | 312 N | 28,679 N | 1.05 |
| C | 31,081 N | 30,128 N | 30,304 N | 30,504 N | 414 N | 31,074 N | 1.02 |
Fig. 8.
Failure characteristics: a) specimen A-type, b) specimen B-type, c) specimen C-type
Tab. 3.
Fracture force values
| 1 (EXP) | 2 (EXP) | 3 (EXP) | EXPavg | EXPSD | FEM | FEM/EXPavg | |
|---|---|---|---|---|---|---|---|
| A | 35,047 N | 36,904 N | 40,121 N | 37,357 N | 2,096 N | 38,358 N | 1.03 |
| B | 37,513 N | 40,139 N | 37,722 N | 38,458 N | 1,192 N | 38,703 N | 1.01 |
| C | 39,800 N | 39,151 N | 40,573 N | 39,841 N | 581 N | 40,463 N | 1.02 |
Fig. 9.
Fracture modes: a) A specimen (FEM), b) A specimen (EXP), c) B specimen (FEM), d) B specimen (EXP), e) C specimen (FEM), c) C specimen (EXP)
Fig. 10.
The fracture stages - ply by ply: a) A-type, b) B-type, c) C-type
Fig. 11.
The fracture phenomenon of A-type composite profile
Fig. 12.
The fracture phenomenon of A-type composite profile - detailed view of the failure form at orientation of the digital microscope head