Issue 45

D. Yang et alii, Frattura ed Integrità Strutturale, 45 (2018) 45-52; DOI: 10.3221/IGF-ESIS.45.04 45 Effects of weld size on stress concentration factors of CHS-CFSHS joints Delei Yang Department of Architectural and Civil Engineering, University of Huanghuai, Zhumadian 463000, China Department of Civil Engineering, University of Ottawa, East Ottawa, ON K1N 6N5, Canada dyang2@uottawa.ca Lewei Tong Department of Building Engineering, Tongji University, Shanghai 200092, China tonglw@tongji.edu.cn A BSTRACT . This paper aims to disclose the effects of weld size on hot spot stress in the calculation of fatigue performance of the joints. For this purpose, the author explored the hot spot stress of CHS-CFSHS T-joints, which consists of circular hollow section (CHS) braces and concrete-filled square hollow section (CFSHS) chords. After reviewing the previous studies and the relevant specifications on weld size, the author probes into the effects of weld size on the stress concentration factor (SCF) of CHS-CFSHS joints via finite- element analysis. The analysis show that the weld size directly affected the hot spot stress in both conditions, and the influence laws were largely the same; with the increase of weld size, the brace-side SCF plunged when the chord- size weld size remained the same, but the chord-side SCF changed slightly when the brace-side weld size was constant; the brace-side and chord-side SCF declined when the brace-side and chord-side weld sizes increased by the same amount. This research successfully determined the weld sizes that are consistent with the relevant specifications, and safe and simple to apply in actual engineering. K EYWORDS . Weld size; Stress concentration factors (SCF); Finite-element analysis; Circular hollow section (CHS); Concrete-filled square hollow section (CFSHS); Welded joints. Citation: Yang, D., Tong, L., Effects of weld size on stress concentration factors of CHS- CFSHS joints, Frattura ed Integrità Strutturale, 45 (2018) 45-52. Received: 07.05.2018 Accepted: 29.05.2018 Published: 01.07.2018 Copyright: © 2018 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION he concrete-filled steel tube (CFST) is a composite member consisting of a steel tube infilled with concrete. With high bearing capacity, good seismic property, strong fire resistance and short construction period, this new structure can satisfy the various needs of modern engineering structures, such as large-span, high altitude, T