Finite element analysis of large diameter high strength octagonal CFST short columns

Abstract Octagonal masonry columns have been broadly used in outstanding architectural heritage due to their aesthetical appearance and to support high loads. Nowadays, concrete-filled steel tubular (CFST) columns have been utilised to carry such high load. However, a recent trend in the construction of the CFST columns is to use the high strength concrete (HSC) to increase the usable floor spaces in different buildings due to the global limited land areas. Therefore, this paper combines the architectural demand of the octagonal column shape with the advantages of the CFST columns by investigating numerically, by means of finite element (FE) modelling, the octagonal CFST short columns. Accordingly, validated FE models for the octagonal CFST short columns are employed to perform parametric studies to widen the available knowledge about their behaviour. The paper is mainly devoted for investigating large diameter columns using extensive series of diameter-to-thickness (D/t) ratios ranging from 40 to 200, most of which filled with HSC up to 100 MPa. The ultimate strengths, based on available experiments in literature and current FE investigation, are compared with the existing design models. This comparison indicates that the existing design models are conservative and their accuracy is affected by the D/t ratios. Therefore, a new design model is suggested based on the existing provisions by taking the D/t ratios of the columns into account. This suggested design model is validated by using the existing experimental results and is found to give excellent results. The important factors that affect the strength and behaviour of the octagonal CFST short columns filled with HSCs are additionally discussed in detail, with new conclusions added to literature for the first time.

[1]  Qing Quan Liang,et al.  Nonlinear Analysis of Concrete-Filled Steel Tubular Columns , 2015 .

[2]  Qing Quan Liang,et al.  Nonlinear analysis of circular concrete-filled steel tubular short columns under eccentric loading , 2009 .

[3]  Toshiyuki Kitada Ultimate strength and ductility of state-of-the-art concrete-filled steel bridge piers in Japan , 1998 .

[4]  R. Chacón Circular concrete-filled tubular columns: state of the art oriented to the vulnerability assessment , 2015 .

[5]  Lin-Hai Han,et al.  Analytical behaviour of concrete-filled double skin steel tubular (CFDST) stub columns , 2010 .

[6]  Y.-K. Yong,et al.  Behavior of Laterally Confined High‐Strength Concrete under Axial Loads , 1988 .

[7]  Lin-Hai Han,et al.  Developments and advanced applications of concrete-filled steel tubular (CFST) structures: Members , 2014 .

[8]  J. G. Macgregor,et al.  Structural Design Considerations for High-Strength Concrete , 1993 .

[9]  Bo Yang,et al.  Plastic and yield slenderness limits for circular concrete filled tubes subjected to static pure bending , 2016 .

[10]  J. Mander,et al.  Theoretical stress strain model for confined concrete , 1988 .

[11]  Yue Wei,et al.  Large diameter concrete-filled high strength steel tubular stub columns under compression , 2016 .

[12]  Mostafa Fahmi Hassanein,et al.  Overall buckling behaviour of circular concrete-filled dual steel tubular columns with stainless steel external tubes , 2017 .

[13]  J. Y. Richard Liew,et al.  Design of Concrete Filled Tubular Beam-columns with High Strength Steel and Concrete , 2016 .

[14]  J. Liew,et al.  Design of High Strength Concrete Filled Tubular Columns For Tall Buildings , 2014 .

[15]  Xianghe Dai,et al.  Numerical modelling of the axial compressive behaviour of short concrete-filled elliptical steel columns , 2010 .

[16]  Qing Quan Liang,et al.  Performance-based analysis of concrete-filled steel tubular beam–columns, Part I: Theory and algorithms , 2009 .

[17]  Fa-xing Ding,et al.  Composite action of octagonal concrete-filled steel tubular stub columns under axial loading , 2016 .

[18]  F. E. Richart,et al.  A study of the failure of concrete under combined compressive stresses , 1928 .

[19]  A. Mirmiran,et al.  Nonlinear finite element modeling of concrete confined by fiber composites , 2000 .

[20]  Arthur H. Nilson,et al.  Spirally Reinforced High-Strength Concrete Columns , 1984 .

[21]  Jianqiao Ye,et al.  A unified formulation for circle and polygon concrete-filled steel tube columns under axial compression , 2013 .

[22]  P. Ronca,et al.  Structural analysis of stone masonry columns of the Basilica S. Maria di Collemaggio , 2016 .

[23]  N. E. Shanmugam,et al.  State of the art report on steel–concrete composite columns , 2001 .

[24]  Brian Uy,et al.  Analysis and design of concrete-filled stiffened thin-walled steel tubular columns under axial compression , 2009 .

[25]  Qing Quan Liang,et al.  Behaviour of circular concrete-filled lean duplex stainless steel tubular short columns , 2013 .

[26]  Brian Uy,et al.  Confined concrete model of circular, elliptical and octagonal CFST short columns , 2016 .

[27]  Tao Yu,et al.  Finite element modeling of confined concrete-I: Drucker–Prager type plasticity model , 2010 .

[28]  Hanbin Ge,et al.  Uniaxial stress–strain relationship of concrete confined by various shaped steel tubes , 2001 .

[29]  Zhong Tao,et al.  Finite element modelling of concrete-filled steel stub columns under axial compression , 2013 .

[30]  Leroy Gardner,et al.  Behaviour and design of square concrete-filled double skin tubular columns with inner circular tubes , 2015 .

[31]  Aci Committe State-of-the-Art Report on High Strength Concrete , 1984 .

[32]  Hiroyuki Nakahara,et al.  Behavior of centrally loaded concrete-filled steel-tube short columns , 2004 .

[33]  Hsuan-Teh Hu,et al.  NONLINEAR ANALYSIS OF AXIALLY LOADED CONCRETE-FILLED TUBE COLUMNS WITH CONFINEMENT EFFECT , 2003 .