Ultimate strength of doubler plate reinforced circular hollow section (CHS) T-joint under elevated temperatures

• Main Author: Zhong, Ai
• Other Authors: Fung Tat Ching
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Civil engineering::Structures and design
• Online Access: http://hdl.handle.net/10356/61161
• Institution: Nanyang Technological University

The structural behavior of doubler plate reinforced circular hollow section (CHS) T-joint under axial compression and out-of-plane bending in elevated temperature was investigated. A finite element model is built and validated using past research results. The ultimate strength of the joint under compression and out-of-plane bending is obtained from force-ovalization curves and moment-rotation curves under different temperatures. Two criteria are used for the compression case; one is by the peak value of the force-ovalization curve, while the other one is by deformation limit proposed by Yura. It is observed that the ultimate strength by Yura limit is lower than the other criteria under the same temperature range. Moreover, instead of setting temperature field in the software, material properties at elevated temperatures are used to save analysis time. Steel properties under different temperature range are studied and its reduction in strength at elevated temperature is proved to be a key factor in CHS T-joint’s ultimate strength reduction. Furthermore, failure modes of the joint are also investigated and compared under various temperatures.