Documents disponibles écrits par cet auteur

Risk consistency and synergy in multihazard design / Chiara Crosti in Journal of structural engineering, Vol. 137 N° 8 (Août 2011) 

Public ISBD [article]  in Journal of structural engineering > Vol. 137 N° 8 (Août 2011) . - pp. 844-849 Titre : Risk consistency and synergy in multihazard design Type de document : texte imprimé Auteurs : Chiara Crosti, Auteur ; Dat Duthinh, Auteur ; Simiu, Emil, Auteur Année de publication : 2011 Article en page(s) : pp. 844-849 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Earthquakes  Moment-resisting  connections  Multihazard  design  Partially  rigid  frames  Risk  consistency  Seismic  design  Steel  frames  Wind Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Current design procedures in the United States use the envelope of individual hazard demands on a structure to ensure safety against multiple hazards. A difficulty in multihazard design for wind and earthquake is that the load and resistance factor method makes use of different design philosophies developed by different subdisciplines. Seismic design explicitly allows for inelastic behavior. In contrast, wind design assumes that, before application of a resistance factor less than unity, the limit state is defined by the development of the first plastic hinge in a structural member. This paper focuses on the issue of risk consistency in multihazard design, and shows that, in spite of this difficulty, it is possible to quantify the risks of arriving at a particular lateral drift state for structures exposed to multiple nonsimultaneous hazards and to compare them to the risks for the same structures subjected to a single hazard. A second focus is the issue of multihazard design synergy. It has been pointed out that redetailing a building to current seismic codes can increase its resistance to blast and that structural efficiency and life-cycle cost are influenced by multihazard considerations. This paper shows that, for the case study of a 10-story steel-frame building, the use of reduced beam section (RBS) connections, intended to enhance ductility in seismic design, does not reduce the risk of structural damage caused by exposure to wind alone or exposure to wind or earthquakes. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i8/p844_s1?isAuthorized=no [article] Risk consistency and synergy in multihazard design [texte imprimé] / Chiara Crosti, Auteur ; Dat Duthinh, Auteur ; Simiu, Emil, Auteur . - 2011 . - pp. 844-849. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 137 N° 8 (Août 2011) . - pp. 844-849 Mots-clés : Earthquakes  Moment-resisting  connections  Multihazard  design  Partially  rigid  frames  Risk  consistency  Seismic  design  Steel  frames  Wind Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Current design procedures in the United States use the envelope of individual hazard demands on a structure to ensure safety against multiple hazards. A difficulty in multihazard design for wind and earthquake is that the load and resistance factor method makes use of different design philosophies developed by different subdisciplines. Seismic design explicitly allows for inelastic behavior. In contrast, wind design assumes that, before application of a resistance factor less than unity, the limit state is defined by the development of the first plastic hinge in a structural member. This paper focuses on the issue of risk consistency in multihazard design, and shows that, in spite of this difficulty, it is possible to quantify the risks of arriving at a particular lateral drift state for structures exposed to multiple nonsimultaneous hazards and to compare them to the risks for the same structures subjected to a single hazard. A second focus is the issue of multihazard design synergy. It has been pointed out that redetailing a building to current seismic codes can increase its resistance to blast and that structural efficiency and life-cycle cost are influenced by multihazard considerations. This paper shows that, for the case study of a 10-story steel-frame building, the use of reduced beam section (RBS) connections, intended to enhance ductility in seismic design, does not reduce the risk of structural damage caused by exposure to wind alone or exposure to wind or earthquakes. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i8/p844_s1?isAuthorized=no

Safety of structures in strong winds and earthquakes / Dat Duthinh in Journal of structural engineering, Vol. 136 N° 3 (Mars 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 3 (Mars 2010) . - pp. 330-333 Titre : Safety of structures in strong winds and earthquakes : multihazard considerations Type de document : texte imprimé Auteurs : Dat Duthinh, Auteur ; Simiu, Emil, Auteur Année de publication : 2011 Article en page(s) : pp. 330-333 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Building  technology  Earthquakes  Limit  states  Multihazards  Safety  Wind  loads Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : In accordance with the ASCE Standard 7-05, in regions subjected to wind and earthquakes, structures are designed for loads induced by wind and, separately, by earthquakes, and the final design is based on the more demanding of these two loading conditions. Implicit in this approach is the belief that the standard assures risks of exceedance of the specified limit states that are essentially identical to the risks inherent in the provisions for regions where only wind or earthquakes occur. We draw the attention of designers, code writers, and insurers to the fact that this belief is, in general, unwarranted, and that ASCE 7 provisions are not risk consistent, i.e., in regions with significant wind and seismic hazards, risks of exceedance of limit states can be up to twice as high as those for regions where one hazard dominates. This conclusion is valid even if the limit states due to wind and earthquake are defined differently, as is the case in ASCE 7. We propose an approach to modifying ASCE 7 provisions which guarantees that risks implicit in minimum ASCE 7 requirements for regions where one hazard dominates are not exceeded for structures in regions with strong wind and seismic hazards. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i3/p330_s1?isAuthorized=no [article] Safety of structures in strong winds and earthquakes : multihazard considerations [texte imprimé] / Dat Duthinh, Auteur ; Simiu, Emil, Auteur . - 2011 . - pp. 330-333. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 3 (Mars 2010) . - pp. 330-333 Mots-clés : Building  technology  Earthquakes  Limit  states  Multihazards  Safety  Wind  loads Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : In accordance with the ASCE Standard 7-05, in regions subjected to wind and earthquakes, structures are designed for loads induced by wind and, separately, by earthquakes, and the final design is based on the more demanding of these two loading conditions. Implicit in this approach is the belief that the standard assures risks of exceedance of the specified limit states that are essentially identical to the risks inherent in the provisions for regions where only wind or earthquakes occur. We draw the attention of designers, code writers, and insurers to the fact that this belief is, in general, unwarranted, and that ASCE 7 provisions are not risk consistent, i.e., in regions with significant wind and seismic hazards, risks of exceedance of limit states can be up to twice as high as those for regions where one hazard dominates. This conclusion is valid even if the limit states due to wind and earthquake are defined differently, as is the case in ASCE 7. We propose an approach to modifying ASCE 7 provisions which guarantees that risks implicit in minimum ASCE 7 requirements for regions where one hazard dominates are not exceeded for structures in regions with strong wind and seismic hazards. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i3/p330_s1?isAuthorized=no

Wind effects on low-rise metal buildings / Bradley F. Coffman 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. 744-748 Titre : Wind effects on low-rise metal buildings : database-assisted design versus ASCE 7-05 standard estimates Type de document : texte imprimé Auteurs : Bradley F. Coffman, Auteur ; Joseph A. Main, Auteur ; Dat Duthinh, Auteur Année de publication : 2011 Article en page(s) : pp. 744-748 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Aerodynamics  Buildings  low-rise  Databases  Structural  design  Wind  forces  Wind  tunnel  tests Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Peak bending moments are compared for a set of steel portal frames of industrial buildings in an open terrain calculated using database-assisted design (DAD) techniques and ASCE 7-05 Standard plots. The comparisons indicate that, depending on the building dimensions, the peak bending moments at the knee based on DAD techniques are generally larger by 10–30% than their counterparts based on the ASCE 7-05 plots. (In one case with a relatively steep roof slope of 26.6° the discrepancies exceed 70%.) For the buildings considered, the discrepancies increase with increasing roof slope and with increasing eave height. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i6/p744_s1?isAuthorized=no [article] Wind effects on low-rise metal buildings : database-assisted design versus ASCE 7-05 standard estimates [texte imprimé] / Bradley F. Coffman, Auteur ; Joseph A. Main, Auteur ; Dat Duthinh, Auteur . - 2011 . - pp. 744-748. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 6 (Juin 2010) . - pp. 744-748 Mots-clés : Aerodynamics  Buildings  low-rise  Databases  Structural  design  Wind  forces  Wind  tunnel  tests Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Peak bending moments are compared for a set of steel portal frames of industrial buildings in an open terrain calculated using database-assisted design (DAD) techniques and ASCE 7-05 Standard plots. The comparisons indicate that, depending on the building dimensions, the peak bending moments at the knee based on DAD techniques are generally larger by 10–30% than their counterparts based on the ASCE 7-05 plots. (In one case with a relatively steep roof slope of 26.6° the discrepancies exceed 70%.) For the buildings considered, the discrepancies increase with increasing roof slope and with increasing eave height. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i6/p744_s1?isAuthorized=no