Confining effect of concrete in double-skinned composite tubular columns

다국어 초록 (Multilingual Abstract)

A double-skinned composite tubular (DSCT) column, which consists of concrete and inner and outer tubes, was finally developed to overcome the weaknesses of concrete filled tube columns by reducing the self-weight of the column and confining the concrete triaxially. Research pertaining to the stiffness and strength of the column and the confining effect in a DSCT column has been carried out. However, detailed studies on the confining stress, especially the internal confining stress in a DSCT column, have not been carried out. Internal and external confining stresses should be evaluated to determine the effective confining stress in a DSCT column. In this paper, the confining stresses of concrete before and after insertion of an inner tube were studied using finite element analysis. The relationship between the internal or external confining stresses and the theoretical confining stress was investigated by parametric studies. New modified formulae for the yield and buckling failure conditions based on the formulae suggested by former researchers were proposed. Through analytical studies, the modified formulae were verified to be effective for economic and reasonable design of the inner tubes in a DSCT column under the same confining stress.

참고문헌 (Reference)

1 임석빈, "구속 조건에 다른 콘크리트 응력-변형률 관계" 대한토목학회 26 (26): 743-752, 2006

2 Kerr, A.D, "The linearization of the prebuckling state and its effects on the determined instability load" 36 (36): 775-785, 1996

3 Alireza Bahrami, "Structural behaviour of tapered concrete-filled steel composite (TCFSC) columns subjected to eccentric loading" 국제구조공학회 9 (9): 403-426, 2012

4 Hayder A. Rasheed, "Software for adaptable eccentric analysis of confined concrete circular columns" 국제구조공학회 10 (10): 331-347, 2012

5 Hsing-Chih Tsai, "Polynomial modeling of confined compressive strength and strain of circular concrete columns" 국제구조공학회 11 (11): 603-620, 2013

6 Wei, S., "Performance of new sandwich tube under axial loading: Experiment" 121 (121): 1806-1814, 1997

7 Han, T.H, "Nonlinear Concrete Model for Double-Skinned Composite Tubular Columns" 24 (24): 2542-2553, 2010

8 Andres W.C. Oreta, "Modeling the confined compressive strength of hybrid circular concrete columns using neural networks" 국제구조공학회 8 (8): 597-616, 2011

9 Rijun Shrestha, "Finite element modelling of FRP-strengthened RC beam-column connections with ANSYS" 국제구조공학회 11 (11): 1-20, 2013

10 Shakir-Khalil, H., "Composite columns of concentric steel tubes" 73-82, 1987

11 Tao, Z., "Behavior of concrete-filled double skin (CHS inner and CHS outer) steel tubular stub columns and beam columns" 60 (60): 1129-1158, 2004

12 Zhong Shan Tong, "Basic Behavior of Centrifugal Hollow Concrete-filled Steel Tube (H-CFST) Stub Columns under Axial Compression" 한국강구조학회 5 (5): 299-304, 2005

13 Shraideh, M.S., "Analysis of steel-GFRP reinforced concrete circular columns" 11 (11): 2013

14 "ABAQUS Manual 6.9.1"