Numerical study of fire resistance of stainless steel circular hollow section columns

2020 ◽  
Vol 38 (2) ◽  
pp. 156-172
Author(s):  
Flávio Arrais ◽  
Nuno Lopes ◽  
Paulo Vila Real
Keyword(s):  
Stainless Steel ◽  
Life Cycle Cost ◽  
Elevated Temperatures ◽  
Numerical Study ◽  
Steel Structures ◽  
Sustainable Construction ◽  
Hollow Section ◽  
Structural Applications ◽  
Eurocode 3 ◽  
Circular Hollow Section

Stainless steel has countless desirable characteristics for a structural material. Although initially more expensive than conventional carbon steel, stainless steel structures can be competitive due to their smaller need for fire protection material and lower life-cycle cost, thus contributing to a more sustainable construction. The most common stainless steel groups used in structural applications are the austenitic, ferritic and austenitic–ferritic (also known as Duplex grades). This work presents a numerical study on the behaviour of stainless steel circular hollow section members under axial compression at elevated temperatures, with different cross-section slenderness. The numerically obtained ultimate load-bearing capacities are compared with simplified calculation formulae from Eurocode 3 for columns under fire situation. A parametric study, considering different stainless steel grades from the aforementioned groups, cross-sectional classes and slendernesses, is here presented for different elevated temperatures. The numerical analyses were performed with the finite element programme SAFIR, with material and geometric non-linear analysis considering imperfections. Comparisons between the numerical results and the Eurocode 3 rules demonstrated that a specific design approach must be developed for stainless steel columns under fire situation.

Fire resistance of stainless steel slender elliptical hollow section beam-columns

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Flávio Alexandre Matias Arrais ◽  
Nuno Lopes ◽  
Paulo Vila Real
Keyword(s):  
Stainless Steel ◽  
Design Methodology ◽  
Elevated Temperatures ◽  
Numerical Study ◽  
Bending Moment ◽  
Content Type ◽  
Hollow Section ◽  
Beam Columns ◽  
Finite Element Software ◽  
Aesthetic Appearance

PurposeStainless steel has different advantages when compared to conventional carbon steel. The corrosion resistance and aesthetic appearance are the most known; however, its better behaviour under elevated temperatures can also be important in buildings design. In spite of the initial cost, stainless-steel application as a structural material has been increasing. Elliptical hollow sections integrate the architectural attributes of the circular hollow sections and the structural advantages of the rectangular hollow sections (RHSs). Hence, the application of stainless-steel material combined with elliptical hollow profiles stands as an interesting design option. The purpose of the paper is to better understand the resistance of stainless-steel-beam columns in case of fireDesign/methodology/approachThe research presents a numerical study on the behaviour of stainless-steel members with slender elliptical hollow section (EHS) subjected to axial compression and bending about the strong axis at elevated temperatures. A parametric numerical study is presented here considering with and without out-of-plane buckling different stainless-steel grades, cross-section and member slenderness, bending moment diagrams and elevated temperatures.FindingsThe tested design methodologies proved to be inadequate for the EHS members being in some situations too conservative.Originality/valueThe safety and accuracy of Eurocode 3 (EC3) design methodology and of a recent design proposal developed for I-sections and cold-formed RHSs are analysed applying material and geometric non-linear analysis considering imperfections with the finite element software SAFIR.

Duplex stainless steel in infrastructure: applications, challenges and opportunities

2019 ◽  
Author(s):  
Nancy Baddoo
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Life Cycle Cost ◽  
Power Plants ◽  
Developing Economies ◽  
High Strength ◽  
Offshore Platforms ◽  
Infrastructure Development ◽  
Structural Applications ◽  
Challenges And Opportunities

<p>Duplex stainless steels have unique properties which can be exploited in a wide variety of applications in the construction industry. The high strength of duplex stainless steel (30% higher than the widely used carbon steel grade S355) leads to specific applications in weight sensitive structures, for example structural members on the topsides of offshore platforms and bridge girders. These applications are usually situated in corrosive environments where durability, combined with long service life, are important and maintenance closures are very costly. Structural applications of duplex stainless steel in the energy and transportation sectors are reviewed. Based on an assessment of the complete supply chain (encompassing design, procurement and fabrication), obstacles to the wider use of structural duplex stainless steel are identified with some recommendations about how they may be overcome. The future burden caused by the use of materials that are not inherently durable in the service environment has led to a growing appreciation that the use of more durable materials in infrastructure applications is the key to maximum availability and low life cycle cost. A huge programme of infrastructure development is needed to meet future demand in both developed and developing economies, which includes the construction of airports, bridges, railways, roads, tunnels and power plants. New opportunities for duplex stainless steel in the creation of resilient, cost-efficient and fit-for purpose energy and transport networks are discussed.</p>

Corrosion Resistance Methods for Stainless Steel

2020 ◽  
pp. 208-225
Author(s):  
Sudesna Roy ◽  
Pramod kumar Mandal
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Stress Corrosion Cracking ◽  
Potentiodynamic Polarization ◽  
Elevated Temperatures ◽  
Corrosion Cracking ◽  
High Mechanical Strength ◽  
Austenitic Structure ◽  
Systemic Analysis ◽  
Structural Applications

304 grade stainless steel is known to be important in most structural applications due to its high mechanical strength, hardness, and machinability. It is considered a versatile steel that has good formability, can be welded as it is, and is non-magnetic austenitic structure. The corrosion resistance is also excellent at room temperature for most corrosive acids and alkalis. However, its corrosion resistance decreases at higher temperatures when exposed to water for prolonged periods of time. It is sensitive to pitting, crevice and stress corrosion cracking at elevated temperatures. In some cases, the resistance is improved by addition of corrosion inhibitor that negatively affects its formability and welding advantages. Therefore, other methods of corrosion protection are desired. This chapter provides in-depth review of corrosion protections materials and methods that have been used for protecting 304SS in different specific applications. It also provides systemic analysis of the potentiodynamic polarization method to compare the corrosion potential of different materials.

Fatigue Detection and Estimation in Martensitic Stainless-Steel Using Magnetic Nondestructive Evaluation Technique

2021 ◽  
Author(s):  
Bharath Basti Shenoy ◽  
Zi Li ◽  
Lalita Udpa ◽  
Satish Udpa ◽  
Yiming Deng ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Magnetic Properties ◽  
Nondestructive Evaluation ◽  
Elevated Temperatures ◽  
Early Stage ◽  
Steel Structures ◽  
Economic Consequences ◽  
Fatigue Detection ◽  
Evaluation Techniques ◽  
Nondestructive Evaluation Techniques

Abstract Stainless steel is used in many applications because of its excellent mechanical properties at elevated temperatures. Material fatigue is a major problem in steel structures and can cause catastrophic damage resulting in significant economic consequences. Conventional nondestructive evaluation techniques can detect macro defects, but do not perform well when it comes to material degradation due to fatigue, which happens at a microstructure level. It is well known that stress applied on a material will have an impact on the microstructure and produces a change in the magnetic properties of the material. Hence magnetic nondestructive evaluation techniques that are sensitive to changes in magnetic properties play a major role in the early-stage fatigue detection, i.e., before the macro crack initiates. This paper introduces the Magnetic Barkhausen Noise technique to garner information about fatigue state of the material under test. Experimental results prove that the sample categories, based on the percentage of remaining fatigue life, can be differentiated using this technique with a system performance slightly over 80%.

scholarly journals A Numerical Investigation on the Structural Behavior of Deficient Steel Frames Strengthened using CFRP Composite

2018 ◽  
Vol 20 (1) ◽  
pp. 1 ◽  
Author(s):  
Amir Hamzah Keykha
Keyword(s):  
Numerical Study ◽  
Load Capacity ◽  
Steel Frames ◽  
Steel Structures ◽  
Independent Study ◽  
Fiber Reinforced Polymers ◽  
Structural Behavior ◽  
Ultimate Load Capacity ◽  
Hollow Section ◽  
Cfrp Composite

Carbon fiber reinforced polymers (CFRP) is one of the materials that is used to strengthen steel structures. Most studies on CFRP strengthening steel on structures have been done on beams and steel columns. No independent study has studied the effect of CFRP strengthening on the structural behavior of steel frames having initial deficiency.The deficiency in steel structures may be created due to the errors caused by construction and others.This study aims to carry out a numerical study on the efficiency of CFRP sheet on strengthening square hollow section (SHS) steel frames having initial deficiency. Seven specimens, five of which were strengthened using CFRP sheets, were analyzed. ANSYS software was used to analyze the SHS steel frames. The results showed that the coverage length, the width, and the number of CFRP layers have a significant effect on increasing and recovering the ultimate load capacity of the SHS steel frames having initial deficiency.

Sign in / Sign up

Export Citation Format

Share Document