Flexural buckling behaviour and residual strengths of S700 high strength steel circular hollow section columns after exposure to fire

• Main Author: Koh, Alicia
• Other Authors: Zhao Ou
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Civil engineering::Structures and design
• Online Access: https://hdl.handle.net/10356/149388
• Institution: Nanyang Technological University

This paper demonstrates the experimental investigation of the flexural buckling behaviour and residual strengths of cold-formed S700 high strength steel (HSS) circular hollow section (CHS) slender columns after being exposed to fire. The experimental study was performed on a total of ten column specimens of two different circular hollow sections. For each section, five column specimens were prepared, with four heated to different levels of elevated temperatures (namely 400 °C, 600 °C, 900 °C, and 1100 °C) and one unheated. The experimental study which includes the furnace tests, material tests, initial global imperfection measurements, and pin-ended column tests was conducted and reported. Due to the absence of post-fire design codes for HSS members, the current design provisions for S700 HSS CHS column members at ambient temperature as set out in Eurocode, American Specification, and Australian Standard were evaluated for their applicability and compatibility to the design of post-fire S700 HSS CHS columns, based on the obtained test results. The evaluation results generally revealed that the Eurocode yields rather conservative but relatively accurate and consistent buckling resistance predictions, while the American Specification and Australian Standard offer a high level of accuracy and consistency.