Influence of Imperfections on Behaviour of Thin-walled Steel-concrete Composite Columns

Deividas Martinavičius,Mindaugas Augonis

doi:10.5755/j02.mech.25935

Abstract

This paper presents experimental and numerical analysis of the composite steel-concrete columns. Three columns are tested experimentally. Overall forty-eight FE models are created. Sixteen different models for every experimental column are analysed to evaluate the influence of the different types of imperfections. It was found that the imperfections reduced the resistance of the composite columns by up to 10 %. Limiting the geometrical imperfection amplitudes to B/200, the steel profile effective cross-sectional area reduction by up to 23 % was observed, while the critical buckling stress was reduced by up to 74 %. Expressions for the calculation of the effective cross-sectional area ratio and critical buckling stress are proposed.

Highlights

Closed section steel-concrete structures are becoming increasingly popular in the construction industry as this type of structures possess various advantages compared to conventional structures
The failure occurred at the mid-height of the columns or in the areas close to end stiffeners
It is found in this research that the residual stresses and geometrical imperfections have a considerable impact on the performance of the composite thin-walled steel-concrete columns

Summary

Introduction

Closed section steel-concrete structures are becoming increasingly popular in the construction industry as this type of structures possess various advantages compared to conventional structures. Composite structures usually have smaller cross-sections than the reinforced concrete structures and are more aesthetic. Smaller cross-sections mean that additional space inside of the building is saved. Steel-concrete structures have a higher fire resistance and stiffness than the regular steel structures. Steel profiles serve a role of a formwork for the concrete. A relatively fast construction of the steel-concrete structures is ensured

Objectives

Discussion

Conclusion