A macro prediction model for butt-welded (U)HSS connections with softened HAZ

Rui Yan, Hui Xie, Fei Yang*, Milan Veljkovic, Xiao lin Zhao

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

23 Downloads (Pure)


This paper reports an investigation on the tensile resistance of fully-penetrated butt-welded connections of (ultra-)high-strength steels considering the strength softening of the heat-affected zone (HAZ) and the strengthening due to the transverse constraint. Firstly, a parametric study is carried out to analyse the tensile behaviour of fully-penetrated butt-welded S700 connections using validated finite element (FE) models. Based on the FE results, the effect of the investigated parameters on the ultimate resistance of the connections is quantified. Consequently, a Macro prediction model is proposed, neglecting the detail of HAZ inhomogeneous microstructures but considering five design parameters, which are the width and thickness of the specimen, the width of HAZ, the softening ratio, and the matching ratio. Finally, the proposed Macro model is validated against the available experimental data of fully-penetrated butt-welded (ultra-)high-strength steel connections in literature. The results show that the Macro model is proven successful in accurately quantifying the effect of HAZ, concerning the strength softening and the transverse constraint strengthening, on the tensile resistance of fully-penetrated butt-welded (ultra-)high-strength steel connections. It is also found that 157 and 96 out of 185 experiments are predicted within a 5% deviation range using the Macro model and prEN 1993-1-8:2021, respectively, proving that the Macro model is more consistent with the experimental data compared to the prediction of prEN 1993-1-8:2021.

Original languageEnglish
Article number108153
Number of pages14
JournalJournal of Constructional Steel Research
Publication statusPublished - 2023

Bibliographical note

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.


  • Fully-penetrated butt weld
  • Heat-affected zone
  • High-strength steel
  • Tensile resistance
  • Transverse constraint
  • Ultra-high-strength steel


Dive into the research topics of 'A macro prediction model for butt-welded (U)HSS connections with softened HAZ'. Together they form a unique fingerprint.

Cite this