Machinery with rotating components poses a challenge to Operational Modal Analysis (OMA) due its periodic inputs, i.e. orders. Transient (acceleration or deceleration) runs represent relevant test condition for structures, which experience low amount of broadband (noise) excitation during operation. In these cases, orders present themselves as favourable source excitation. However, this type ca...

The modes of linear time invariant mechanical systems can be estimated from output-only vibration measurements under ambient excitation conditions with subspace-based system identification methods. In the presence additional unmeasured periodic excitation, for example due to rotating machinery, described by a state-space model where input dynamics appear as subsystem in addition structural inte...

investigations on vibration behaviors of railway track systems were attempted in this research. this was made by conducting a comprehensive field investigation into the free vibration of track systems and response of tracks to train moving loads. in-situ modal analysis was used in a railway track field as an efficient method of investigating dynamic properties of railway track systems. natural ...