Material relationship identification for finite element analysis at intermediate strain rates using optical measurements

Start Page
459
End Page
468
Citation
Progress in the Analysis and Design of Marine Structures MARSTRUCT: 459-468 (2017-05)
Contribution to Conference
6th International Conference on Marine Structures, MARSTRUCT 2017 
Publisher DOI
10.1201/9781315157368-53
Scopus ID
2-s2.0-85035041801
Accidental events, the interaction with ice as well as, in case of navy, detonations can lead to plastic deformations including fracture of ship structures. For the finite element analysis of such events, a suitable description for the material relationship is required. Therefore, this paper presents a procedure to obtain the effective stress-strain material relationship at intermediate strain rates. The corresponding uniaxial tensile tests are carried out at different speeds in order to investigate strain-rate effects. Since mechanical extensometers are not suitable for high speed tensile testing a high speed optical strain measurement system and a corresponding evaluation routine in MATLAB are developed. Two measuring marks are applied on the specimen and optically traced by a high speed camera. Based on the result of these measurements, a novel approach to determine effective stress-strain relations for the implementation into finite element models is proposed and compared with current approaches.