000013654 001__ 13654
000013654 005__ 20161114170126.0
000013654 04107 $$aeng
000013654 046__ $$k2011-05-25
000013654 100__ $$aKwak H., G.
000013654 24500 $$aDevelopment of Nonlinear Hysteresis Model for Concrete Filled Steel Tube Column

000013654 24630 $$n3.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000013654 260__ $$bNational Technical University of Athens, 2011
000013654 506__ $$arestricted
000013654 520__ $$2eng$$aConcrete filled steel tube(CFT) is a round or rectangular steel pipe structure filled up with concrete. The confinement effect of concrete due to surrounding steel tube causes triaxial stress state which improves strength and ductility of concrete. Therefore this type of structure has many benefits over steel or reinforced concrete columns such as improved performance of stiffness, load capacity and energy absorption. Moreover outer steel tube can be used for casting of concrete. Considering those advantages, applications of CFT are increasing and a number of studies have been conducted. As a result, various methods to analytically evaluate the performance of CFT are developed. The main purpose of this study is developing the nonlinear model for CFT which can estimate not static strength but hysteresis behavior. As CFT columns may fail due to not only material failure in a section but also instability of the structure, more rigorous numerical are required in order to secure their strength and serviceability. To this end, nonlinear analysis model which take into account both material and geometric nonlinearity is developed. For a reinforced concrete, cracking of concrete and yielding of surrounding steel tube are main causes of material nonlinearity. But in the case of the CFT, material behavior is significantly changes along stress level due to confinement effect. Considering its frequent applicability to high-rise buildings, geometric nonlinearity due to the P-∆ effect must be considered. The fiber section approach was adopted for section analysis because it requires only uniaxial stress strain relation which was frequently developed and improved through former researchers. An incremental-iterative numerical scheme based on arc-length method is adopted to ensure displacement controlled nonlinearity. Material property for both concrete and steel can consider loading/unloading path. Therefore hysteresis behavior of structure can be examined. Through comparison of the obtained numerical results with experimental data, the introduced numerical model is validated. Developed numerical model can be used for evaluating both ultimate strength and force-displacement relation of CFT. Unlike RC columns, force-displacement relation to calculate absorbed energy is more important for CFT. Because improved energy absorption capacity is advantageous for resisting earthquake loading. References [1] Susantha Kas, Ge H, Usami, T, Uniaxial stress-strain relationship of concrete confined by various shaped steel tubes. Engineering Structures. 23,1331-47, 2001. [2] Lakshmi B, Shanmugam N E, Nonlinear Analysis of In-Filled Steel-Concrete Composite Columns, Journal of Structural Engineering. ASCE, 128, 7, 922-933. 2002. [3] H.G. Kwak, J.K. Kim, P-∆ effect of slender RC columns under seismic load. Engineering Structures, 29, 11, 3121-3133, 2007.

000013654 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000013654 653__ $$a

000013654 7112_ $$aCOMPDYN 2011 - 3rd International Thematic Conference$$cIsland of Corfu (GR)$$d2011-05-25 / 2011-05-28$$gCOMPDYN2011
000013654 720__ $$aKwak H., G.$$iKwak J., H.
000013654 8560_ $$ffischerc@itam.cas.cz
000013654 8564_ $$s16857$$uhttps://invenio.itam.cas.cz/record/13654/files/445.pdf$$yOriginal version of the author's contribution as presented on CD, section: RS 05 FEM: Modelling and Simulation  .
000013654 962__ $$r13401
000013654 980__ $$aPAPER