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Damage process of thin-walled laminated structures made of modern laminates can be tested using
experimental or numerical methods. It is difficult to achieve high repeatability and accuracy of the
real thin-walled structures during the production process. The real column in experimental studies
is not perfect, whereas its numerical model of the samples is perfect. Therefore, it is difficult to
compare the experimental and numerical results. The solutions obtained by both methods can be
differ significantly. Additionally, incompatibility of damage mechanism can be found in many cases
of experimental studies. The main aim of this study was prepared FEM model of the real structures
and simulations its collapse process. Therefore, the 3D Atos core scanner and special GOM soft was
used to prepare the geometrical model of the real structure. Additionally, this software allowed to
estimate surface inaccuracies, geometric dimensions of the real objects. Next, experimental collapse
analysis of tested thin walled columns on a Zwick Z100 static materials testing machine was performed.
The real samples were subjected to uniform axial shortening. The tested columns were loaded with
the load from 0 to the maximal load, which allowed one to observe the column behavior until its
collapse. Experimental tests were performed at a constant velocity of the cross-bar equal to 1 mm/min.
All analyzed samples were made with carbon-epoxy laminate using autoclave technique. The lay-up
configurations of the laminate was [60,02,-602,603,-602,03,-602,0,602]T, where direction 0 was along
the length of the column. Material parameters of laminate were Young’s modulus along the fiber
direction: 170000MPa and along the fiber transverse direction: 7600MPa; shear modulus: 3520MPa;
Poisson’s ratio: 0.36. The length of the column was 300 mm. Thickness of the column was 0.81mm
and its width of the flanges was 40mm. Non-linear numeric simulations were performed by the Newton-
Raphson method until ultimate failure of the structure using Abaqus software. Composite material
damage was described with a progressive damage model. Whereby, it was possible to identify the
mechanism of damage. Finally, all obtained results for real structures were compared. The influence
of geometrical imperfections on failure process of the real column and its mechanism of collapse were
discussed. The present study was supported by statutory resources allowed to the Department of
Applied Mechanics, the Lublin University of Technology under "The Grant for Young Researchers" no.
FNM 30/IM/2020.
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