Elevated-temperature material properties and fracture behavior of fire-resistant steel FR355

• Published in: Journal of Building Engineering 2024-09, Vol.92, p.109540, Article 109540
• Main Authors: Cho, Yonghyun, Park, Min Jae, Ahn, Jaekwon, Ryu, Eunmi
• Format: Article
• Language: English
• Subjects: Ductile fracture; Elevated-temperature material properties; Fire; Fire-resistant steel; True stress-strain model
• ISSN: 2352-7102; 2352-7102
• DOI: 10.1016/j.jobe.2024.109540

Fire-resistant steel (FRS) has been increasingly used in engineering structures due to their advantages of excellent earthquake and fire resistance properties. Accurately characterization of material properties and limit states of steel material is very important for structural-safety design and finite element (FE) simulation. This paper presents the results of experimental and numerical investigations on the elevated-temperature performance of FRS in terms of material properties, full-range true stress-strain curve, ductile fracture behavior, which has not yet been reported. The experimental part of the present paper includes the steady-state tensile testing of conventional structural steel (CSS) and FRS at temperatures up to 800 °C. Hollomon law and weighted average method were adopted to derive full-range true stress-strain behavior of the investigated steels at elevated temperatures, which is required for ductile fracture simulation in ABAQUS. Ductile fracture of tensile coupon specimens was modelled using the stress-modified critical strain model (SMCS). To verify the accuracy and application of the proposed true stress-strain and fracture models, finite element (FE) simulations of tensile coupon tests were performed using ABAQUS/explicit. It shows that the FE simulation incorporating proposed material plastic behavior and ductile fracture model provides accurate predictions for fracture response of the tensile coupons. •Investigated the elevated-temperature material properties of FR355 steel.•Investigated the range of applicability of the current fire design codes.•Identified full-range true stress-strain curves for fracture simulations of FR355 steel exposed to high temperatures.•Proposed ductile fracture model to simulate the fracture of tensile coupons specimens.