Documents disponibles écrits par cet auteur

Direct strength design of cold-formed C-sections for shear and combined actions / Cao Hung Pham in Journal of structural engineering, Vol. 138 N° 6 (Juin 2012) 

Public ISBD [article]  in Journal of structural engineering > Vol. 138 N° 6 (Juin 2012) . - pp. 759–768 Titre : Direct strength design of cold-formed C-sections for shear and combined actions Type de document : texte imprimé Auteurs : Cao Hung Pham, Auteur ; Gregory J. Hancock, Auteur Année de publication : 2012 Article en page(s) : pp. 759–768 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Cold-formed  High  strength  steel  Direct  strength  method  Effective  width  method  Shear  test  Combined  bending  and  shear  Tension  field  action  Reliability Résumé : The direct strength method (DSM) recently included in the North American Specification and Australian/New Zealand Standard AS/NZS 4600:2005 gives design rules for compression and bending. No rules are presented in this standard for shear or for combined bending and shear. Two series of tests on C-section can be used to develop and calibrate rules for design in shear and for combined bending and shear. These are the University of Missouri Rolla tests of the 1970s and recent tests on high-strength C-sections at the University of Sydney. Both series of tests use a similar test rig, although different levels of tension field action have been observed. Two features researched are the effect of full-section shear buckling (as opposed to web-only shear buckling), and tension field action. Full-section buckling is a feature of the DSM but requires software that can evaluate full sections for shear. The paper proposes DSM design rules for C-sections in shear and for combined bending and shear both with and without tension field action. The test results are compared with the proposed design rules. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000510 [article] Direct strength design of cold-formed C-sections for shear and combined actions [texte imprimé] / Cao Hung Pham, Auteur ; Gregory J. Hancock, Auteur . - 2012 . - pp. 759–768. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 138 N° 6 (Juin 2012) . - pp. 759–768 Mots-clés : Cold-formed  High  strength  steel  Direct  strength  method  Effective  width  method  Shear  test  Combined  bending  and  shear  Tension  field  action  Reliability Résumé : The direct strength method (DSM) recently included in the North American Specification and Australian/New Zealand Standard AS/NZS 4600:2005 gives design rules for compression and bending. No rules are presented in this standard for shear or for combined bending and shear. Two series of tests on C-section can be used to develop and calibrate rules for design in shear and for combined bending and shear. These are the University of Missouri Rolla tests of the 1970s and recent tests on high-strength C-sections at the University of Sydney. Both series of tests use a similar test rig, although different levels of tension field action have been observed. Two features researched are the effect of full-section shear buckling (as opposed to web-only shear buckling), and tension field action. Full-section buckling is a feature of the DSM but requires software that can evaluate full sections for shear. The paper proposes DSM design rules for C-sections in shear and for combined bending and shear both with and without tension field action. The test results are compared with the proposed design rules. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000510

Experimental investigation of high strength cold-formed C-sections in combined bending and shear / Cao Hung Pham in Journal of structural engineering, Vol. 136 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 7 (Juillet 2010) . - pp. 866-878 Titre : Experimental investigation of high strength cold-formed C-sections in combined bending and shear Type de document : texte imprimé Auteurs : Cao Hung Pham, Auteur ; Gregory J. Hancock, Auteur Année de publication : 2011 Article en page(s) : pp. 866-878 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : High  strength  steel  Direct  strength  method  Effective  width  method  Combined  bending  and  shear  Shear  test  Tension  field  action Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : In roof systems, a high strength steel profiled sheeting fastened to high strength steel cold-formed purlins of a lipped C- or Z-section is commonly used throughout the world. The design of such systems is performed according to the provisions of the limit states Australia/New Zealand Standard for Cold-Formed Steel Structures in Australia and the North American Specification for the Design of Cold-Formed Steel Structural Members in the United States. In both standards, which include the newly developed direct strength method of design (DSM), the method presented is limited to pure compression and pure bending. The situations of pure shear and combined bending and shear as occurs in a continuous purlin system are not considered. In order to extend the DSM to purlin systems, three different test series on high strength cold-formed C-section purlins have been performed at the University of Sydney. The test series include predominantly shear, combined bending and shear, and bending only test series. Two different section depths and three different thicknesses of the lipped channel section were tested in this study. Further, tests with and without torsion/distortion restraint straps screwed on the top flanges adjacent to the loading points were also considered. This paper summarizes the test results and formulas developed from the effective width method and the DSM. Proposals for design are included in this paper. Comparisons with the Australian Steel Structures Standard are also included to take account of the tension field action. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i7/p866_s1?isAuthorized=no [article] Experimental investigation of high strength cold-formed C-sections in combined bending and shear [texte imprimé] / Cao Hung Pham, Auteur ; Gregory J. Hancock, Auteur . - 2011 . - pp. 866-878. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 7 (Juillet 2010) . - pp. 866-878 Mots-clés : High  strength  steel  Direct  strength  method  Effective  width  method  Combined  bending  and  shear  Shear  test  Tension  field  action Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : In roof systems, a high strength steel profiled sheeting fastened to high strength steel cold-formed purlins of a lipped C- or Z-section is commonly used throughout the world. The design of such systems is performed according to the provisions of the limit states Australia/New Zealand Standard for Cold-Formed Steel Structures in Australia and the North American Specification for the Design of Cold-Formed Steel Structural Members in the United States. In both standards, which include the newly developed direct strength method of design (DSM), the method presented is limited to pure compression and pure bending. The situations of pure shear and combined bending and shear as occurs in a continuous purlin system are not considered. In order to extend the DSM to purlin systems, three different test series on high strength cold-formed C-section purlins have been performed at the University of Sydney. The test series include predominantly shear, combined bending and shear, and bending only test series. Two different section depths and three different thicknesses of the lipped channel section were tested in this study. Further, tests with and without torsion/distortion restraint straps screwed on the top flanges adjacent to the loading points were also considered. This paper summarizes the test results and formulas developed from the effective width method and the DSM. Proposals for design are included in this paper. Comparisons with the Australian Steel Structures Standard are also included to take account of the tension field action. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i7/p866_s1?isAuthorized=no

Experimental study of high-strength cold-formed stiffened-web c-sections in compression / Derrick C. Y. Yap in Journal of structural engineering, Vol. 137 N° 2 (Fevrier 2011) 

Public ISBD [article]  in Journal of structural engineering > Vol. 137 N° 2 (Fevrier 2011) . - pp. 162-172 Titre : Experimental study of high-strength cold-formed stiffened-web c-sections in compression Type de document : texte imprimé Auteurs : Derrick C. Y. Yap, Auteur ; Gregory J. Hancock, Auteur Année de publication : 2011 Article en page(s) : pp. 162-172 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Cold  formed  High-strength  steel  Local  buckling  Distortional  buckling  Interaction  buckling  Postbuckling  behavior  Intermediately  stiffened  section Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : High-strength cold-formed steel sections are commonly used in a variety of applications including residential construction. These steel sections typically have a nominal yield stress of 550 MPa and the use of such high-strength material allows for a reduction in thicknesses. With this reduction in thickness, the high-strength steel can be manufactured into complex shapes including stiffeners. Such complex shapes exhibit structural instabilities such as local, distortional, and flexural-torsional buckling modes, and in some cases, interaction of the local and distortional buckling modes may occur. This paper describes the design and testing of web-stiffened high-strength steel cold-formed lipped channel columns. In order to be able to apply the direct strength method (DSM) in Section 7 of the Australian Standard AS/NZS 4600:2005 and Appendix 1 of the North American Specification to design, the steel sections must be prequalified as a compression member. The section chosen is prequalified and has nearly coincidental local buckling and distortional buckling loads as well as a flexural-torsional mode which varies with length. A series of compression tests was carried out in a 300-kN capacity SINTEC testing machine over a range of lengths with fixed-ended conditions. The varying lengths were chosen so as to observe the buckling modes and the possibility of interaction between them. The effect of the different types of failure modes is also discussed in this paper. The experimental results are then compared with design methods in the existing design standards. The methods include the effective width method and the DSM as described in the Australian Cold-Formed Steel Structures Standard and the North American Specification. It is shown that the existing standards are unconservative and new proposals for dealing with this are made. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i2/p162_s1?isAuthorized=no [article] Experimental study of high-strength cold-formed stiffened-web c-sections in compression [texte imprimé] / Derrick C. Y. Yap, Auteur ; Gregory J. Hancock, Auteur . - 2011 . - pp. 162-172. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 137 N° 2 (Fevrier 2011) . - pp. 162-172 Mots-clés : Cold  formed  High-strength  steel  Local  buckling  Distortional  buckling  Interaction  buckling  Postbuckling  behavior  Intermediately  stiffened  section Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : High-strength cold-formed steel sections are commonly used in a variety of applications including residential construction. These steel sections typically have a nominal yield stress of 550 MPa and the use of such high-strength material allows for a reduction in thicknesses. With this reduction in thickness, the high-strength steel can be manufactured into complex shapes including stiffeners. Such complex shapes exhibit structural instabilities such as local, distortional, and flexural-torsional buckling modes, and in some cases, interaction of the local and distortional buckling modes may occur. This paper describes the design and testing of web-stiffened high-strength steel cold-formed lipped channel columns. In order to be able to apply the direct strength method (DSM) in Section 7 of the Australian Standard AS/NZS 4600:2005 and Appendix 1 of the North American Specification to design, the steel sections must be prequalified as a compression member. The section chosen is prequalified and has nearly coincidental local buckling and distortional buckling loads as well as a flexural-torsional mode which varies with length. A series of compression tests was carried out in a 300-kN capacity SINTEC testing machine over a range of lengths with fixed-ended conditions. The varying lengths were chosen so as to observe the buckling modes and the possibility of interaction between them. The effect of the different types of failure modes is also discussed in this paper. The experimental results are then compared with design methods in the existing design standards. The methods include the effective width method and the DSM as described in the Australian Cold-Formed Steel Structures Standard and the North American Specification. It is shown that the existing standards are unconservative and new proposals for dealing with this are made. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i2/p162_s1?isAuthorized=no