TY  - JOUR
A1  - Abdelnour, Mena
A1  - Zabel, Volkmar
T1  - Modal identification of structures with a dynamic behaviour characterised by global and local modes at close frequencies
JF  - Acta Mechanica
N2  - Identification of modal parameters of a space frame structure is a complex assignment due to a large number of degrees of freedom, close natural frequencies, and different vibrating mechanisms. Research has been carried out on the modal identification of rather simple truss structures. So far, less attention has been given to complex three-dimensional truss structures. This work develops a vibration-based methodology for determining modal information of three-dimensional space truss structures. The method uses a relatively complex space truss structure for its verification. Numerical modelling of the system gives modal information about the expected vibration behaviour. The identification process involves closely spaced modes that are characterised by local and global vibration mechanisms. To distinguish between local and global vibrations of the system, modal strain energies are used as an indicator. The experimental validation, which incorporated a modal analysis employing the stochastic subspace identification method, has confirmed that considering relatively high model orders is required to identify specific mode shapes. Especially in the case of the determination of local deformation modes of space truss members, higher model orders have to be taken into account than in the modal identification of most other types of structures.
KW  - Fachwerkbau
KW  - Holzkonstruktion
KW  - Schwingung
KW  - three-dimensional truss structures
KW  - vibration-based methodology
KW  - numerical modelling
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20230525-63822
UR  - https://link.springer.com/article/10.1007/s00707-023-03598-z
VL  - 2023
SP  - 1
EP  - 21
PB  - Springer
CY  - Wien
ER  - 
TY  - JOUR
A1  - Galffy, Mozes
A1  - Wellmann Jelic, Andres
A1  - Hartmann, Dietrich
T1  - Lifetime-oriented modelling of vortex-induced across-wind vibrations on bridge tie rods
N2  - The influence of vortex-induces vibrations on vertical tie rods has been proved as a determinant load factor in the lifetime-oriented dimensioning of arched steel bridges. Particularly, the welded connection plates between the suspenders and the arches often exhibit cracks induced primarily rods. In this context, the synchronization of the vortex-shedding to the rod motion in a critical wind velocity range, the so-called lock-in effect, is of essential interest.
KW  - Finite-Elemente-Methode
KW  - Physikalisches Verfahren
KW  - Brückenbau
KW  - Schwingung
Y1  - 2004
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-2536
ER  -