Documents disponibles écrits par cet auteur

Control structure interaction of electromagnetic mass damper system for structural vibration control / Chunwei Zhang in Journal of engineering mechanics, Vol. 134 N°5 (Mai 2008) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 134 N°5 (Mai 2008) . - pp. 428–437 Titre : Control structure interaction of electromagnetic mass damper system for structural vibration control Type de document : texte imprimé Auteurs : Chunwei Zhang, Auteur ; Jinping Ou, Auteur Année de publication : 2008 Article en page(s) : pp. 428–437 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Vibration  Damping  Control  systems  Shake  table  tests  Structural  control  Interaction  models Résumé : To investigate the effect of control-structure-interaction (CSI) between the innovative electromagnetic mass damper (EMD) control system and the test structure, three computational models are first developed in this paper. Then, typical driving voltages are applied to the servo-amplifier of the EMD system to excite the structure and to examine the dynamic behavior of the EMD system when it is implemented into the structure. Furthermore, the test results are compared with the predictions based on the proposed parametric models, namely on-line examination. Finally, shaking table tests of structural seismic response control employing the EMD control system are conducted to validate and compare the effectiveness of those parametric models. All the test results have shown that only when the CSI effect (especially the higher-order CSI effect) is fully considered, can the on-line dynamical property of the EMD system be accurately predicted and its control performance fully exerted. This is essential to achieve the highest performance when employing such EMD systems in suppressing structural vibrations. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%290733-9399%282008%29134%3A5%2842 [...] [article] Control structure interaction of electromagnetic mass damper system for structural vibration control [texte imprimé] / Chunwei Zhang, Auteur ; Jinping Ou, Auteur . - 2008 . - pp. 428–437. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 134 N°5 (Mai 2008) . - pp. 428–437 Mots-clés : Vibration  Damping  Control  systems  Shake  table  tests  Structural  control  Interaction  models Résumé : To investigate the effect of control-structure-interaction (CSI) between the innovative electromagnetic mass damper (EMD) control system and the test structure, three computational models are first developed in this paper. Then, typical driving voltages are applied to the servo-amplifier of the EMD system to excite the structure and to examine the dynamic behavior of the EMD system when it is implemented into the structure. Furthermore, the test results are compared with the predictions based on the proposed parametric models, namely on-line examination. Finally, shaking table tests of structural seismic response control employing the EMD control system are conducted to validate and compare the effectiveness of those parametric models. All the test results have shown that only when the CSI effect (especially the higher-order CSI effect) is fully considered, can the on-line dynamical property of the EMD system be accurately predicted and its control performance fully exerted. This is essential to achieve the highest performance when employing such EMD systems in suppressing structural vibrations. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%290733-9399%282008%29134%3A5%2842 [...]

Flexural demand on pin-connected buckling-restrained braces and design recommendations / Junxian Zhao in Journal of structural engineering, Vol. 138 N° 11 (Novembre 2012) 

Public ISBD [article]  in Journal of structural engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1398-1415 Titre : Flexural demand on pin-connected buckling-restrained braces and design recommendations Type de document : texte imprimé Auteurs : Junxian Zhao, Auteur ; Wu, Bin, Auteur ; Jinping Ou, Auteur Année de publication : 2013 Article en page(s) : pp. 1398-1415 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Buckling-restrained  brace  Pinned  connection  Core  projection  Brace  end  rotation  Two-point  contact  Flexural  demand Résumé : In a previous study by the authors, the cyclic behavior of a novel type of pin-connected angle steel buckling-restrained brace (ABRB) was examined, and the failure mechanism in the core projection of the ABRB induced by an excessive bending effect caused by end rotation was discussed. In this paper, the occurrence mechanism of end rotation modes and the bending effect in the core projection of an ABRB are first investigated based on the previous test results, which shows that end rotation demands would be significantly increased with the presence of a gap and an additional bending effect could be observed if the end rotation demands were large enough to cause two-point contact at the core ends. Then, a new method to predict the flexural demand on pin-connected BRBs is proposed by considering the effect of the end rotation modes, clearance, initial eccentricity, and initial deflection of casing. The design criteria to prevent yielding of the core projection are presented and further verified by the previous test results. Furthermore, the effects of key influential parameters on the flexural demand on core projection are discussed based on the analytical results. It is found that such a bending effect can be significantly reduced by decreasing the gap or increasing the constrained length of the core stiffening segment. The C-mode end rotation with single curvature bending configuration is found to be generally the most unfavorable case for core projection design. Finally, several design recommendations are provided for pin-connected BRBs. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000549 [article] Flexural demand on pin-connected buckling-restrained braces and design recommendations [texte imprimé] / Junxian Zhao, Auteur ; Wu, Bin, Auteur ; Jinping Ou, Auteur . - 2013 . - pp. 1398-1415. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1398-1415 Mots-clés : Buckling-restrained  brace  Pinned  connection  Core  projection  Brace  end  rotation  Two-point  contact  Flexural  demand Résumé : In a previous study by the authors, the cyclic behavior of a novel type of pin-connected angle steel buckling-restrained brace (ABRB) was examined, and the failure mechanism in the core projection of the ABRB induced by an excessive bending effect caused by end rotation was discussed. In this paper, the occurrence mechanism of end rotation modes and the bending effect in the core projection of an ABRB are first investigated based on the previous test results, which shows that end rotation demands would be significantly increased with the presence of a gap and an additional bending effect could be observed if the end rotation demands were large enough to cause two-point contact at the core ends. Then, a new method to predict the flexural demand on pin-connected BRBs is proposed by considering the effect of the end rotation modes, clearance, initial eccentricity, and initial deflection of casing. The design criteria to prevent yielding of the core projection are presented and further verified by the previous test results. Furthermore, the effects of key influential parameters on the flexural demand on core projection are discussed based on the analytical results. It is found that such a bending effect can be significantly reduced by decreasing the gap or increasing the constrained length of the core stiffening segment. The C-mode end rotation with single curvature bending configuration is found to be generally the most unfavorable case for core projection design. Finally, several design recommendations are provided for pin-connected BRBs. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000549