Derivation of the unified equation of axial compression of CFST columns

Ruoyang Zhou,Xiaoxiong Zha,P Zhou,R Weerasinghe,Y He

doi:10.1051/e3sconf/202014301004

Ruoyang Zhou, Xiaoxiong Zha + Show 3 more

Open Access

https://doi.org/10.1051/e3sconf/202014301004

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Abstract

The steel tube concrete columns with steel reinforcement cages, steel plates and steel tubes has been used in super high-rise buildings, which are called concrete-filled steel tubular (CFST) columns with internal stiffeners. Based on the theory of limit equilibrium, the unified equation for the axial bearing capacity of the CFST columns with internal stiffeners is obtained. The derived equation in this study can provide reference for the future engineering applications.

Highlights

As the height of the structure increases, the vertical load of the structure will inevitably increase
concrete-filled steel tubular (CFST) columns with novel cross section have been used in super high-rise building
Comparing with ordinary CFST columns, these types of columns have the following advantages: First, for the super-large section, the internal stiffeners can divide the section into multiple hollow section, which can effectively reduce the section size of the concrete column and prevent the unfavorable appearance of the large concrete cross section

Summary

Introduction

As the height of the structure increases, the vertical load of the structure will inevitably increase. Comparing with ordinary CFST columns, these types of columns have the following advantages: First, for the super-large section, the internal stiffeners can divide the section into multiple hollow section, which can effectively reduce the section size of the concrete column and prevent the unfavorable appearance of the large concrete cross section. These hollow sections form a composite peripheral constraint on concrete, which can improve the peripheral constraint and global ductility of concrete. A unified equation for investigating the axial bearing capacity of CFST columns with internal stiffeners that benefits from the limit equilibrium theory to derive the bearing capacity of the axial compression is proposed

Derivation of the equation for the axial compression

Fundamental hypothesis

Derivation of the unified equation

Conclusion