Documents disponibles écrits par cet auteur

Detecting multiple open cracks in elastic beams by static tests / Salvatore Caddemi in Journal of engineering mechanics, Vol. 137 N° 2 (Fevrier 2011) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 137 N° 2 (Fevrier 2011) . - pp.113-124 Titre : Detecting multiple open cracks in elastic beams by static tests Type de document : texte imprimé Auteurs : Salvatore Caddemi, Auteur ; Morassi, Antonino, Auteur Année de publication : 2011 Article en page(s) : pp.113-124 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Damage  detection  Beams  Static  loads  Cracks  Inverse  problems Résumé : This paper concerns with the identification of multiple open cracks in a beam by measurements of the damage-induced variations in the static deflection of the beam under a prescribed load condition. Each crack is simulated by an equivalent linear spring connecting the two adjacent segments of beam. Sufficient conditions on the static measurements which allow for the unique identification of the damage are presented and discussed for nonuniform beams under some ideal boundary conditions. The inverse analysis is based on an explicit expression of the crack-induced variation in the deflection of the beam under a given load distribution and it provides exact closed-form expressions of position and severity of the cracks in terms of the measured data. The theoretical results are confirmed by a comparison with static tests carried out on a steel beam with localized damages. REFERENCE : 0733-9399 DEWEY : 620.1 En ligne : http://ascelibrary.org/emo/resource/1/jenmdt/v137/i2/p113_s1?isAuthorized=no [article] Detecting multiple open cracks in elastic beams by static tests [texte imprimé] / Salvatore Caddemi, Auteur ; Morassi, Antonino, Auteur . - 2011 . - pp.113-124. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 137 N° 2 (Fevrier 2011) . - pp.113-124 Mots-clés : Damage  detection  Beams  Static  loads  Cracks  Inverse  problems Résumé : This paper concerns with the identification of multiple open cracks in a beam by measurements of the damage-induced variations in the static deflection of the beam under a prescribed load condition. Each crack is simulated by an equivalent linear spring connecting the two adjacent segments of beam. Sufficient conditions on the static measurements which allow for the unique identification of the damage are presented and discussed for nonuniform beams under some ideal boundary conditions. The inverse analysis is based on an explicit expression of the crack-induced variation in the deflection of the beam under a given load distribution and it provides exact closed-form expressions of position and severity of the cracks in terms of the measured data. The theoretical results are confirmed by a comparison with static tests carried out on a steel beam with localized damages. REFERENCE : 0733-9399 DEWEY : 620.1 En ligne : http://ascelibrary.org/emo/resource/1/jenmdt/v137/i2/p113_s1?isAuthorized=no

Dynamic identification of a concrete bridge with orthotropic plate-type deck / Andrea Marcuzzi in Journal of structural engineering, Vol. 136 N° 5 (Mai 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 5 (Mai 2010) . - pp. 586-602 Titre : Dynamic identification of a concrete bridge with orthotropic plate-type deck Type de document : texte imprimé Auteurs : Andrea Marcuzzi, Auteur ; Morassi, Antonino, Auteur Année de publication : 2011 Article en page(s) : pp. 586-602 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Dynamic  tests  Bridge  Concrete  Identification  Structural  models Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : This paper continues a line of research aimed at the development of a dynamically based health condition monitoring of bridge structures in the area of Friuli Venezia Giulia, Italy. One subject of this research program has been a two-span highway bridge with a concrete slab supported by closely spaced precast beams, a constructive typology which is quite diffuse in the regional highway network. Forced-vibration tests and experimental modal analysis were used to determine the vibration properties of the structure. An identification procedure based on dynamic data allowed to define an accurate orthotropic plate model of the deck and to improve the description of some constructional details in the finite-element model of the bridge such as the boundary conditions on abutments and the connection between the deck and pier. The usefulness of the combined experimental and analytical process in the identification of structural properties has been proven and the procedure can be applied to other structures of the same typology. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i5/p586_s1?isAuthorized=no [article] Dynamic identification of a concrete bridge with orthotropic plate-type deck [texte imprimé] / Andrea Marcuzzi, Auteur ; Morassi, Antonino, Auteur . - 2011 . - pp. 586-602. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 5 (Mai 2010) . - pp. 586-602 Mots-clés : Dynamic  tests  Bridge  Concrete  Identification  Structural  models Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : This paper continues a line of research aimed at the development of a dynamically based health condition monitoring of bridge structures in the area of Friuli Venezia Giulia, Italy. One subject of this research program has been a two-span highway bridge with a concrete slab supported by closely spaced precast beams, a constructive typology which is quite diffuse in the regional highway network. Forced-vibration tests and experimental modal analysis were used to determine the vibration properties of the structure. An identification procedure based on dynamic data allowed to define an accurate orthotropic plate model of the deck and to improve the description of some constructional details in the finite-element model of the bridge such as the boundary conditions on abutments and the connection between the deck and pier. The usefulness of the combined experimental and analytical process in the identification of structural properties has been proven and the procedure can be applied to other structures of the same typology. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i5/p586_s1?isAuthorized=no

Dynamic testing and structural identification of the hypo bank office complex / Morassi, Antonino in Journal of structural engineering, Vol. 137 N° 12 (Décembre 2011) 

Public ISBD [article]  in Journal of structural engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1527-1539 Titre : Dynamic testing and structural identification of the hypo bank office complex : I: Experiments Type de document : texte imprimé Auteurs : Morassi, Antonino, Auteur Année de publication : 2012 Article en page(s) : pp. 1527-1539 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Dynamic  methods  Structural  identification  Buildings  Experimental  modal  analysis  Finite-element  models  Structural  dynamics Résumé : Nondestructive dynamic methods are a useful tool in structural engineering. Their purpose is twofold. First, they provide guidance on the validation of a mathematical model of the structure under investigation. Second, repeated tests over time can indicate the emergence of possible damage occurring during the structure’s lifetime. Recent technological progress has generated extremely accurate and reliable experimental methods, enabling a good estimate of dynamic behavior of a structural system. Although experimental techniques are now well-established, the interpretation of measurements still lags somewhat behind. This particularly concerns structural identification due to its nature of inverse problem. In addition, when identification techniques are applied to the study of real-world structures, additional obstacles arise given the complexity of the structural behavior, the inaccuracy of the analytical models used to interpret experiments, measurement errors, and incomplete field data. This study discusses some of these aspects with reference to a series of harmonic forced-vibration tests carried out on the new headquarters of the Hypo Bank (Tavagnacco, northeast Italy). The special structural typology of the tilted building and the complex distribution of the resisting structural members have made interesting, and at the same time quite complicated, the interpretation of the real dynamic behavior of the construction. The present paper (Part I) is devoted to the experimental programme. The use of the measured dynamic data in the calibration of numerical models of the Hypo Bank complex is presented and discussed in Part II. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i12/p1527_s1?isAuthorized=no [article] Dynamic testing and structural identification of the hypo bank office complex : I: Experiments [texte imprimé] / Morassi, Antonino, Auteur . - 2012 . - pp. 1527-1539. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1527-1539 Mots-clés : Dynamic  methods  Structural  identification  Buildings  Experimental  modal  analysis  Finite-element  models  Structural  dynamics Résumé : Nondestructive dynamic methods are a useful tool in structural engineering. Their purpose is twofold. First, they provide guidance on the validation of a mathematical model of the structure under investigation. Second, repeated tests over time can indicate the emergence of possible damage occurring during the structure’s lifetime. Recent technological progress has generated extremely accurate and reliable experimental methods, enabling a good estimate of dynamic behavior of a structural system. Although experimental techniques are now well-established, the interpretation of measurements still lags somewhat behind. This particularly concerns structural identification due to its nature of inverse problem. In addition, when identification techniques are applied to the study of real-world structures, additional obstacles arise given the complexity of the structural behavior, the inaccuracy of the analytical models used to interpret experiments, measurement errors, and incomplete field data. This study discusses some of these aspects with reference to a series of harmonic forced-vibration tests carried out on the new headquarters of the Hypo Bank (Tavagnacco, northeast Italy). The special structural typology of the tilted building and the complex distribution of the resisting structural members have made interesting, and at the same time quite complicated, the interpretation of the real dynamic behavior of the construction. The present paper (Part I) is devoted to the experimental programme. The use of the measured dynamic data in the calibration of numerical models of the Hypo Bank complex is presented and discussed in Part II. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i12/p1527_s1?isAuthorized=no

Dynamic testing and structural identification of the hypo bank office complex / Morassi, Antonino in Journal of structural engineering, Vol. 137 N° 12 (Décembre 2011) 

Public ISBD [article]  in Journal of structural engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1540-1552 Titre : Dynamic testing and structural identification of the hypo bank office complex : II: Identification Type de document : texte imprimé Auteurs : Morassi, Antonino, Auteur ; Francesco Polentarutti, Auteur Année de publication : 2012 Article en page(s) : pp. 1540-1552 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Dynamic  methods  Structural  identification  Buildings  Experimental  modal  analysis  Finite-element  models  Structural  dynamics Résumé : The Hypo Bank headquarters complex, a structure formed by two adjacent seven-story buildings, was subjected to a series of harmonic forced vibration tests in August 2005. In Part I of this research, the natural frequencies, damping factors, and three-dimensional shapes of the first vibration modes of each building were estimated. In this paper, the experimental characteristics are compared with those predicted by a preliminary finite-element model. The properties of vibration modes with prevailing amplitudes along the longer side of the complex are described with poor precision. This large disagreement has suggested that, in spite of the presence of the seismic joint between the two buildings, some coupling through the joint should be considered to predict the dynamic behavior of the whole complex reasonably well. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i12/p1540_s1?isAuthorized=no [article] Dynamic testing and structural identification of the hypo bank office complex : II: Identification [texte imprimé] / Morassi, Antonino, Auteur ; Francesco Polentarutti, Auteur . - 2012 . - pp. 1540-1552. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1540-1552 Mots-clés : Dynamic  methods  Structural  identification  Buildings  Experimental  modal  analysis  Finite-element  models  Structural  dynamics Résumé : The Hypo Bank headquarters complex, a structure formed by two adjacent seven-story buildings, was subjected to a series of harmonic forced vibration tests in August 2005. In Part I of this research, the natural frequencies, damping factors, and three-dimensional shapes of the first vibration modes of each building were estimated. In this paper, the experimental characteristics are compared with those predicted by a preliminary finite-element model. The properties of vibration modes with prevailing amplitudes along the longer side of the complex are described with poor precision. This large disagreement has suggested that, in spite of the presence of the seismic joint between the two buildings, some coupling through the joint should be considered to predict the dynamic behavior of the whole complex reasonably well. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i12/p1540_s1?isAuthorized=no

Reconstruction method for damage detection in beams based on natural frequency and antiresonant frequency measurements / Dilena, Michele in Journal of engineering mechanics, Vol. 136 N° 3 (Mars 2010) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 136 N° 3 (Mars 2010) . - pp. 329-344 Titre : Reconstruction method for damage detection in beams based on natural frequency and antiresonant frequency measurements Type de document : texte imprimé Auteurs : Dilena, Michele, Auteur ; Morassi, Antonino, Auteur Article en page(s) : pp. 329-344 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Damage  Vibration  Natural  frequency  Reconstruction  Measurement. Résumé : This paper deals with a dynamic method for damage detection in beams. Under the assumption that the damaged beam is a perturbation of the undamaged one, it is shown that natural frequency and antiresonant frequency shifts induced by structural damage contain information on certain generalized Fourier coefficients of the stiffness variation caused by the degradation. A reconstruction method based on this property is proposed to solve the inverse problem. Cases with pseudoexperimental and experimental data are discussed. The results are in good agreement with the theory, provided that average frequency and antiresonant frequency shifts are bigger than modeling/measurement errors. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...] [article] Reconstruction method for damage detection in beams based on natural frequency and antiresonant frequency measurements [texte imprimé] / Dilena, Michele, Auteur ; Morassi, Antonino, Auteur . - pp. 329-344. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 136 N° 3 (Mars 2010) . - pp. 329-344 Mots-clés : Damage  Vibration  Natural  frequency  Reconstruction  Measurement. Résumé : This paper deals with a dynamic method for damage detection in beams. Under the assumption that the damaged beam is a perturbation of the undamaged one, it is shown that natural frequency and antiresonant frequency shifts induced by structural damage contain information on certain generalized Fourier coefficients of the stiffness variation caused by the degradation. A reconstruction method based on this property is proposed to solve the inverse problem. Cases with pseudoexperimental and experimental data are discussed. The results are in good agreement with the theory, provided that average frequency and antiresonant frequency shifts are bigger than modeling/measurement errors. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]