Matches in SemOpenAlex for { <https://semopenalex.org/work/W80497981> ?p ?o ?g. }
- W80497981 abstract "Among the experimental methods commonly used to define the behaviour of a full scale system, dynamic tests are the most complete and efficient procedures. A dynamic test is an experimental process, which would define a set of characteristic parameters of the dynamic behaviour of the system, such as natural frequencies of the structure, mode shapes and the corresponding modal damping values associated. An assessment of these modal characteristics can be used both to verify the theoretical assumptions of the project, to monitor the performance of the structural system during its operational use. The thesis is structured in the following chapters: The first introductive chapter recalls some basic notions of dynamics of structure, focusing the discussion on the problem of systems with multiply degrees of freedom (MDOF), which can represent a generic real system under study, when it is excited with harmonic force or in free vibration. The second chapter is entirely centred on to the problem of dynamic identification process of a structure, if it is subjected to an experimental test in forced vibrations. It first describes the construction of FRF through classical FFT of the recorded signal. A different method, also in the frequency domain, is subsequently introduced; it allows accurately to compute the FRF using the geometric characteristics of the ellipse that represents the direct input-output comparison. The two methods are compared and then the attention is focused on some advantages of the proposed methodology. The third chapter focuses on the study of real structures when they are subjected to experimental test, where the force is not known, like in an ambient or impact test. In this analysis we decided to use the CWT, which allows a simultaneous investigation in the time and frequency domain of a generic signal x(t). The CWT is first introduced to process free oscillations, with excellent results both in terms of frequencies, dampings and vibration modes. The application in the case of ambient vibrations defines accurate modal parameters of the system, although on the damping some important observations should be made. The fourth chapter is still on the problem of post processing data acquired after a vibration test, but this time through the application of discrete wavelet transform (DWT). In the first part the results obtained by the DWT are compared with those obtained by the application of CWT. Particular attention is given to the use of DWT as a tool for filtering the recorded signal, in fact in case of ambient vibrations the signals are often affected by the presence of a significant level of noise. The fifth chapter focuses on another important aspect of the identification process: the model updating. In this chapter, starting from the modal parameters obtained from some environmental vibration tests, performed by the University of Porto in 2008 and the University of Sheffild on the Humber Bridge in England, a FE model of the bridge is defined, in order to define what type of model is able to capture more accurately the real dynamic behaviour of the bridge. The sixth chapter outlines the necessary conclusions of the presented research. They concern the application of a method in the frequency domain in order to evaluate the modal parameters of a structure and its advantages, the advantages in applying a procedure based on the use of wavelet transforms in the process of identification in tests with unknown input and finally the problem of 3D modeling of systems with many degrees of freedom and with different types of uncertainty." @default.
- W80497981 created "2016-06-24" @default.
- W80497981 creator A5030423954 @default.
- W80497981 date "2010-05-31" @default.
- W80497981 modified "2023-09-24" @default.
- W80497981 title "Dynamic identification of structures: experimental assessment of modal parameteres through methods in frequency domain, in time-frequency domain and model updating" @default.
- W80497981 doi "https://doi.org/10.6092/unibo/amsdottorato/3108" @default.
- W80497981 hasPublicationYear "2010" @default.
- W80497981 type Work @default.
- W80497981 sameAs 80497981 @default.
- W80497981 citedByCount "0" @default.
- W80497981 crossrefType "dissertation" @default.
- W80497981 hasAuthorship W80497981A5030423954 @default.
- W80497981 hasConcept C103824480 @default.
- W80497981 hasConcept C104286136 @default.
- W80497981 hasConcept C111919701 @default.
- W80497981 hasConcept C11413529 @default.
- W80497981 hasConcept C116834253 @default.
- W80497981 hasConcept C119247159 @default.
- W80497981 hasConcept C119599485 @default.
- W80497981 hasConcept C121332964 @default.
- W80497981 hasConcept C127413603 @default.
- W80497981 hasConcept C135628077 @default.
- W80497981 hasConcept C178736951 @default.
- W80497981 hasConcept C185592680 @default.
- W80497981 hasConcept C188027245 @default.
- W80497981 hasConcept C19118579 @default.
- W80497981 hasConcept C198394728 @default.
- W80497981 hasConcept C198824145 @default.
- W80497981 hasConcept C200239387 @default.
- W80497981 hasConcept C24890656 @default.
- W80497981 hasConcept C2524010 @default.
- W80497981 hasConcept C2776960193 @default.
- W80497981 hasConcept C2780009758 @default.
- W80497981 hasConcept C31972630 @default.
- W80497981 hasConcept C33923547 @default.
- W80497981 hasConcept C41008148 @default.
- W80497981 hasConcept C59822182 @default.
- W80497981 hasConcept C66938386 @default.
- W80497981 hasConcept C71139939 @default.
- W80497981 hasConcept C74261601 @default.
- W80497981 hasConcept C75172450 @default.
- W80497981 hasConcept C77088390 @default.
- W80497981 hasConcept C78736273 @default.
- W80497981 hasConcept C8590192 @default.
- W80497981 hasConcept C86803240 @default.
- W80497981 hasConcept C98045186 @default.
- W80497981 hasConceptScore W80497981C103824480 @default.
- W80497981 hasConceptScore W80497981C104286136 @default.
- W80497981 hasConceptScore W80497981C111919701 @default.
- W80497981 hasConceptScore W80497981C11413529 @default.
- W80497981 hasConceptScore W80497981C116834253 @default.
- W80497981 hasConceptScore W80497981C119247159 @default.
- W80497981 hasConceptScore W80497981C119599485 @default.
- W80497981 hasConceptScore W80497981C121332964 @default.
- W80497981 hasConceptScore W80497981C127413603 @default.
- W80497981 hasConceptScore W80497981C135628077 @default.
- W80497981 hasConceptScore W80497981C178736951 @default.
- W80497981 hasConceptScore W80497981C185592680 @default.
- W80497981 hasConceptScore W80497981C188027245 @default.
- W80497981 hasConceptScore W80497981C19118579 @default.
- W80497981 hasConceptScore W80497981C198394728 @default.
- W80497981 hasConceptScore W80497981C198824145 @default.
- W80497981 hasConceptScore W80497981C200239387 @default.
- W80497981 hasConceptScore W80497981C24890656 @default.
- W80497981 hasConceptScore W80497981C2524010 @default.
- W80497981 hasConceptScore W80497981C2776960193 @default.
- W80497981 hasConceptScore W80497981C2780009758 @default.
- W80497981 hasConceptScore W80497981C31972630 @default.
- W80497981 hasConceptScore W80497981C33923547 @default.
- W80497981 hasConceptScore W80497981C41008148 @default.
- W80497981 hasConceptScore W80497981C59822182 @default.
- W80497981 hasConceptScore W80497981C66938386 @default.
- W80497981 hasConceptScore W80497981C71139939 @default.
- W80497981 hasConceptScore W80497981C74261601 @default.
- W80497981 hasConceptScore W80497981C75172450 @default.
- W80497981 hasConceptScore W80497981C77088390 @default.
- W80497981 hasConceptScore W80497981C78736273 @default.
- W80497981 hasConceptScore W80497981C8590192 @default.
- W80497981 hasConceptScore W80497981C86803240 @default.
- W80497981 hasConceptScore W80497981C98045186 @default.
- W80497981 hasLocation W804979811 @default.
- W80497981 hasOpenAccess W80497981 @default.
- W80497981 hasPrimaryLocation W804979811 @default.
- W80497981 hasRelatedWork W1504784742 @default.
- W80497981 hasRelatedWork W2005373046 @default.
- W80497981 hasRelatedWork W2010597013 @default.
- W80497981 hasRelatedWork W2036412494 @default.
- W80497981 hasRelatedWork W2060981633 @default.
- W80497981 hasRelatedWork W2086001195 @default.
- W80497981 hasRelatedWork W2092382146 @default.
- W80497981 hasRelatedWork W2094317768 @default.
- W80497981 hasRelatedWork W2132404479 @default.
- W80497981 hasRelatedWork W2342057683 @default.
- W80497981 hasRelatedWork W2613548049 @default.
- W80497981 hasRelatedWork W2731596225 @default.
- W80497981 hasRelatedWork W2792898314 @default.
- W80497981 hasRelatedWork W2895433515 @default.
- W80497981 hasRelatedWork W2997226520 @default.
- W80497981 hasRelatedWork W3025834532 @default.