Stainless steel angle section members in compression and combined loading

Abstract

Recently, architect pay more attention to the life-cycle cost of the structure except the aesthetic appearance. Due to high corrosion resistance, ease of maintenance as well as construction, also the high recycle rate of stainless steel members, the cold-formed stainless steel members satisfy the requirements of the architect, and are being widely used in civil engineering. Especially for the severe environment which required high corrosion resistance, the stainless steel is an ideal choice in such situation. For instance, the power transmission tower which can be located in some marine environment can use the stainless steel and popular section for this application is angle section. The use of stainless steel in load-bearing constructions is increasing, but the behavior of this material in structures has not been as accurately described as for carbon steel. The main difference between these two materials is the stress-stain curve, for stainless steel, it has high stain hardening ratio, while also a high nonlinear performance even at low stress levels. For carbon steel, it has a quite linear stage before yielding, but strain hardening is not as significant as stainless steel. Now most of published papers about stainless steel structural members are concentrated on hollow sections like RHS, CHS or H section, which are double symmetric sections. The primary aim of this thesis was to study the behavior of angle section columns and beam columns, to find if there is any need to propose some modifications to the code on the design of this section. The particularity of this section is that it is a monosymmetric section, except the flexural buckling, it can occur torsion and torsion flexural buckling as well. The main part of this thesis is using a numerical model for parametric studies and deal with the data from these analyses to reach reliable conclusions. In order to make sure the numerical model is accurate to some extent, FE models were created and validated according to existing tests and also a simple column test which is carried out in the laboratory in the Czech Technical University in Prague. Finally, some modifications were proposed to compression buckling curve and interaction curve which are used to design beam column.

Recently, architect pay more attention to the life-cycle cost of the structure except the aesthetic appearance. Due to high corrosion resistance, ease of maintenance as well as construction, also the high recycle rate of stainless steel members, the cold-formed stainless steel members satisfy the requirements of the architect, and are being widely used in civil engineering. Especially for the severe environment which required high corrosion resistance, the stainless steel is an ideal choice in such situation. For instance, the power transmission tower which can be located in some marine environment can use the stainless steel and popular section for this application is angle section. The use of stainless steel in load-bearing constructions is increasing, but the behavior of this material in structures has not been as accurately described as for carbon steel. The main difference between these two materials is the stress-stain curve, for stainless steel, it has high stain hardening ratio, while also a high nonlinear performance even at low stress levels. For carbon steel, it has a quite linear stage before yielding, but strain hardening is not as significant as stainless steel. Now most of published papers about stainless steel structural members are concentrated on hollow sections like RHS, CHS or H section, which are double symmetric sections. The primary aim of this thesis was to study the behavior of angle section columns and beam columns, to find if there is any need to propose some modifications to the code on the design of this section. The particularity of this section is that it is a monosymmetric section, except the flexural buckling, it can occur torsion and torsion flexural buckling as well. The main part of this thesis is using a numerical model for parametric studies and deal with the data from these analyses to reach reliable conclusions. In order to make sure the numerical model is accurate to some extent, FE models were created and validated according to existing tests and also a simple column test which is carried out in the laboratory in the Czech Technical University in Prague. Finally, some modifications were proposed to compression buckling curve and interaction curve which are used to design beam column.