Modal contribution and state space order selection in operational modal analysis

Operational Modal Analysis using Second-Order Blind Identification

For modal analysis of large structures, it is unpractical and expensive to use artificial excitation (e.g., shakers). However, engineering structures are most often subject to ambient loads (e.g., traffic and wind) that can be exploited for modal parameter estimation. One difficulty is that the actual loading conditions cannot generally be measured, and output-only measurements are available. T...

Polymax: a Revolution in Operational Modal Analysis

Recently the superior performance of the PolyMAX modal parameter estimation method using frequency response functions was demonstrated. The method can be implemented in a very similar way as the industry standard polyreference (time-domain) least-squares complex exponential method: in a first step a stabilisation diagram is constructed containing frequency, damping and participation information...

Damping Estimation using Operational Modal Analysis

It has been observed that even though modal frequencies are well estimated using Operational Modal Analysis (OMA) techniques, damping estimation is not as accurate. The opinions on this aspect of OMA have been widely varying and no consensus or definite answers are available. In this paper the OMA procedure, data processing and modal parameter estimation, is studied with respect to proper dampi...

Frequency Domain Techniques for Operational Modal Analysis

Operational Modal Analysis, also known as Output Only Modal Analysis, has in the recent years, been used for determination of modal parameters of civil engineering structures and is now becoming widely used also for mechanical structures. The advantage of the method is that no artificial excitation needs to be applied to the structure, or force signals to be measured. In this paper, the non-par...

Modal analysis of structures in periodic state