Documents disponibles écrits par cet auteur

Investigation of the sliding behavior between steel and mortar for seismic applications in structures / Jason McCormick in Earthquake engineering structural dynamics, Vol. 38 N° 12 (Octobre 2009) 

Public ISBD [article]  in Earthquake engineering structural dynamics > Vol. 38 N° 12 (Octobre 2009) . - pp. 1401-1419 Titre : Investigation of the sliding behavior between steel and mortar for seismic applications in structures Type de document : texte imprimé Auteurs : Jason McCormick, Auteur ; Nagae, Takuya, Auteur ; Masahiro Ikenaga Article en page(s) : pp. 1401-1419 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Friction;  steel;  Mortar;  Steel  structures;  Shake  table  tests;  Seismic Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : The friction developed between a steel base plate and a mortar base contributes shear resistance to the building system during a seismic event. In order to investigate the possible sliding behavior between the base plate and the mortar, a shake table study is undertaken using a large rigid mass supported by steel contact elements which rest on mortar surfaces connected to the shake table. Horizontal input accelerations are considered at various magnitudes and frequencies. The results provide a constant friction coefficient during sliding with an average value of approximately 0.78. A theoretical formulation of the friction behavior is also undertaken. The theoretical equations show that the sliding behavior is dependent on the ratio of the friction force to the input force. The addition of vertical accelerations to the system further complicates the sliding behavior as a result of the varying normal force. This results in a variable friction resistance which is a function of the amplitude, phase, and frequency of the horizontal and vertical input motions. In general, this study showed a consistent and reliable sliding behavior between steel and mortar. ISSN : 0098-8847 En ligne : www.interscience.wiley.com/journal/eqe [article] Investigation of the sliding behavior between steel and mortar for seismic applications in structures [texte imprimé] / Jason McCormick, Auteur ; Nagae, Takuya, Auteur ; Masahiro Ikenaga . - pp. 1401-1419. Génie Civil Langues : Anglais (eng) in Earthquake engineering structural dynamics > Vol. 38 N° 12 (Octobre 2009) . - pp. 1401-1419 Mots-clés : Friction;  steel;  Mortar;  Steel  structures;  Shake  table  tests;  Seismic Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : The friction developed between a steel base plate and a mortar base contributes shear resistance to the building system during a seismic event. In order to investigate the possible sliding behavior between the base plate and the mortar, a shake table study is undertaken using a large rigid mass supported by steel contact elements which rest on mortar surfaces connected to the shake table. Horizontal input accelerations are considered at various magnitudes and frequencies. The results provide a constant friction coefficient during sliding with an average value of approximately 0.78. A theoretical formulation of the friction behavior is also undertaken. The theoretical equations show that the sliding behavior is dependent on the ratio of the friction force to the input force. The addition of vertical accelerations to the system further complicates the sliding behavior as a result of the varying normal force. This results in a variable friction resistance which is a function of the amplitude, phase, and frequency of the horizontal and vertical input motions. In general, this study showed a consistent and reliable sliding behavior between steel and mortar. ISSN : 0098-8847 En ligne : www.interscience.wiley.com/journal/eqe

Seismic resistance capacity of high-rise buildings subjected to long-period ground motions / Chun-Yu, Lin in Journal of structural engineering, Vol. 136 N° 6 (Juin 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 6 (Juin 2010) . - pp. 637-644 Titre : Seismic resistance capacity of high-rise buildings subjected to long-period ground motions : E-defense shaking table test Type de document : texte imprimé Auteurs : Chun-Yu, Lin, Auteur ; Nagae, Takuya, Auteur ; Toko Hitaka, Auteur Année de publication : 2011 Article en page(s) : pp. 637-644 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : High-rise  building  Long-period  ground  motion  Shaking  table  test  Seismic  performance  Beam-to-column  connections Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : A series of large-scale shaking table tests is conducted for a high-rise building structure subjected to long-period ground motions. A test method is developed to preserve the original dimensions of structural members of a prototype building that has 21 stories with a total height of 80 m. The test specimen consists of a four-story, two-span by one-bay steel moment frame and three substitute layers placed on top of the moment frame. The substitute layers, which consist of concrete slabs and rubber bearings, are arranged to represent the upper stories of the prototype. From preliminary vibration tests, equivalence between the test specimen and the prototype is verified in terms of the lower mode natural periods and corresponding mode shapes. The test specimen when subjected to long-period ground motions exhibits cumulative ductilities more than four times those expected in Japanese seismic design, while the maximum story drifts remain nearly the same as those considered in the design. A number of cyclic inelastic deformations caused fractures at the bottom flanges of beam ends. According to these observations, the combination of large cumulative ductility demand, the weld quality of the field weld connections, and the promotion of strain concentrations at the toe of the bottom flange weld access hole by the presence of floor slabs caused the fractures and resultant smaller cumulative ductility relative to that observed in the bare beam tests. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i6/p637_s1?isAuthorized=no [article] Seismic resistance capacity of high-rise buildings subjected to long-period ground motions : E-defense shaking table test [texte imprimé] / Chun-Yu, Lin, Auteur ; Nagae, Takuya, Auteur ; Toko Hitaka, Auteur . - 2011 . - pp. 637-644. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 6 (Juin 2010) . - pp. 637-644 Mots-clés : High-rise  building  Long-period  ground  motion  Shaking  table  test  Seismic  performance  Beam-to-column  connections Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : A series of large-scale shaking table tests is conducted for a high-rise building structure subjected to long-period ground motions. A test method is developed to preserve the original dimensions of structural members of a prototype building that has 21 stories with a total height of 80 m. The test specimen consists of a four-story, two-span by one-bay steel moment frame and three substitute layers placed on top of the moment frame. The substitute layers, which consist of concrete slabs and rubber bearings, are arranged to represent the upper stories of the prototype. From preliminary vibration tests, equivalence between the test specimen and the prototype is verified in terms of the lower mode natural periods and corresponding mode shapes. The test specimen when subjected to long-period ground motions exhibits cumulative ductilities more than four times those expected in Japanese seismic design, while the maximum story drifts remain nearly the same as those considered in the design. A number of cyclic inelastic deformations caused fractures at the bottom flanges of beam ends. According to these observations, the combination of large cumulative ductility demand, the weld quality of the field weld connections, and the promotion of strain concentrations at the toe of the bottom flange weld access hole by the presence of floor slabs caused the fractures and resultant smaller cumulative ductility relative to that observed in the bare beam tests. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i6/p637_s1?isAuthorized=no

A substructure shaking table test for reproduction of earthquake responses of high-rise buildings / Ji, Xiaodong in Earthquake engineering structural dynamics, Vol. 38 N° 12 (Octobre 2009) 

Public ISBD [article]  in Earthquake engineering structural dynamics > Vol. 38 N° 12 (Octobre 2009) . - pp. 1381-1399 Titre : A substructure shaking table test for reproduction of earthquake responses of high-rise buildings Type de document : texte imprimé Auteurs : Ji, Xiaodong, Auteur ; Kajiwara, Kouichi, Auteur ; Nagae, Takuya, Auteur ; Ryuta Enokida ; Nakashima, Masayoshi Article en page(s) : pp. 1381-1399 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Shaking  table  test;  Substructure;  IDCS  algorithm;  Model  matching  method;  H  method;  high-rise  building Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : When subjected to long-period ground motions, high-rise buildings' upper floors undergo large responses. Furniture and nonstructural components are susceptible to significant damage in such events. This paper proposes a full-scale substructure shaking table test to reproduce large floor responses of high-rise buildings. The response at the top floor of a virtual 30-story building model subjected to a synthesized long-period ground motion is taken as a target wave for reproduction. Since a shaking table has difficulties in directly reproducing such large responses due to various capacity limitations, a rubber-and-mass system is proposed to amplify the table motion. To achieve an accurate reproduction of the floor responses, a control algorithm called the open-loop inverse dynamics compensation via simulation (IDCS) algorithm is used to generate a special input wave for the shaking table. To implement the IDCS algorithm, the model matching method and the H method are adopted to construct the controller. A numerical example is presented to illustrate the open-loop IDCS algorithm and compare the performance of different methods of controller design. A series of full-scale substructure shaking table tests are conducted in E-Defense to verify the effectiveness of the proposed method and examine the seismic behavior of furniture. The test results demonstrate that the rubber-and-mass system is capable of amplifying the table motion by a factor of about 3.5 for the maximum velocity and displacement, and the substructure shaking table test can reproduce the large floor responses for a few minutes ISSN : 0098-8847 En ligne : www.interscience.wiley.com/journal/eqe [article] A substructure shaking table test for reproduction of earthquake responses of high-rise buildings [texte imprimé] / Ji, Xiaodong, Auteur ; Kajiwara, Kouichi, Auteur ; Nagae, Takuya, Auteur ; Ryuta Enokida ; Nakashima, Masayoshi . - pp. 1381-1399. Génie Civil Langues : Anglais (eng) in Earthquake engineering structural dynamics > Vol. 38 N° 12 (Octobre 2009) . - pp. 1381-1399 Mots-clés : Shaking  table  test;  Substructure;  IDCS  algorithm;  Model  matching  method;  H  method;  high-rise  building Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : When subjected to long-period ground motions, high-rise buildings' upper floors undergo large responses. Furniture and nonstructural components are susceptible to significant damage in such events. This paper proposes a full-scale substructure shaking table test to reproduce large floor responses of high-rise buildings. The response at the top floor of a virtual 30-story building model subjected to a synthesized long-period ground motion is taken as a target wave for reproduction. Since a shaking table has difficulties in directly reproducing such large responses due to various capacity limitations, a rubber-and-mass system is proposed to amplify the table motion. To achieve an accurate reproduction of the floor responses, a control algorithm called the open-loop inverse dynamics compensation via simulation (IDCS) algorithm is used to generate a special input wave for the shaking table. To implement the IDCS algorithm, the model matching method and the H method are adopted to construct the controller. A numerical example is presented to illustrate the open-loop IDCS algorithm and compare the performance of different methods of controller design. A series of full-scale substructure shaking table tests are conducted in E-Defense to verify the effectiveness of the proposed method and examine the seismic behavior of furniture. The test results demonstrate that the rubber-and-mass system is capable of amplifying the table motion by a factor of about 3.5 for the maximum velocity and displacement, and the substructure shaking table test can reproduce the large floor responses for a few minutes ISSN : 0098-8847 En ligne : www.interscience.wiley.com/journal/eqe