[article]
Titre : |
Long-term behavior of composite beams under positive and negative bending. I, Experimental study |
Type de document : |
texte imprimé |
Auteurs : |
Jiansheng Fan, Auteur ; Jianguo Nie, Auteur ; Quanwang Li, Auteur |
Année de publication : |
2011 |
Article en page(s) : |
pp. 849-857 |
Note générale : |
Génie Civil |
Langues : |
Anglais (eng) |
Mots-clés : |
Shrinkage Creep Crack Composite steel-concrete beam Long-term test |
Index. décimale : |
624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes |
Résumé : |
This paper presents an experimental program designed to examine the long-term behavior of composite steel-concrete beams under sustained loads. The test program consisted of two simply supported beams under positive bending moments and two cantilever beams under negative bending moments. Long-term deflections, strains, and the cracking behaviors of the specimen beams were monitored over a period of 3 years. The primary observations are: (1) the deflection of the simply supported beam under positive bending moment increased quite significantly over the time due to creep and shrinkage, with the midspan deflections after 3 years of loading reached 2.5 times of the initial deflections, and (2) the cracking of concrete occurred in hogging moment regions for cantilever beams due to the combined effects of concrete shrinkage and sustained negative bending moments. Current design codes were evaluated through a comparison between the calculations and testing results. It was found that the effective modulus method provides a satisfactory prediction on deflections and strains for beams under positive bending moments. But for beams under negative bending moment, the stiffness reduction due to cracking effect should be considered in calculation.
|
DEWEY : |
624.17 |
ISSN : |
0733-9445 |
En ligne : |
http://ascelibrary.org/sto/resource/1/jsendh/v136/i7/p849_s1?isAuthorized=no |
in Journal of structural engineering > Vol. 136 N° 7 (Juillet 2010) . - pp. 849-857
[article] Long-term behavior of composite beams under positive and negative bending. I, Experimental study [texte imprimé] / Jiansheng Fan, Auteur ; Jianguo Nie, Auteur ; Quanwang Li, Auteur . - 2011 . - pp. 849-857. Génie Civil Langues : Anglais ( eng) in Journal of structural engineering > Vol. 136 N° 7 (Juillet 2010) . - pp. 849-857
Mots-clés : |
Shrinkage Creep Crack Composite steel-concrete beam Long-term test |
Index. décimale : |
624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes |
Résumé : |
This paper presents an experimental program designed to examine the long-term behavior of composite steel-concrete beams under sustained loads. The test program consisted of two simply supported beams under positive bending moments and two cantilever beams under negative bending moments. Long-term deflections, strains, and the cracking behaviors of the specimen beams were monitored over a period of 3 years. The primary observations are: (1) the deflection of the simply supported beam under positive bending moment increased quite significantly over the time due to creep and shrinkage, with the midspan deflections after 3 years of loading reached 2.5 times of the initial deflections, and (2) the cracking of concrete occurred in hogging moment regions for cantilever beams due to the combined effects of concrete shrinkage and sustained negative bending moments. Current design codes were evaluated through a comparison between the calculations and testing results. It was found that the effective modulus method provides a satisfactory prediction on deflections and strains for beams under positive bending moments. But for beams under negative bending moment, the stiffness reduction due to cracking effect should be considered in calculation.
|
DEWEY : |
624.17 |
ISSN : |
0733-9445 |
En ligne : |
http://ascelibrary.org/sto/resource/1/jsendh/v136/i7/p849_s1?isAuthorized=no |
|