Static capacity of collar plate reinforced tubular X-connections subjected to compressive loading: study of geometrical effects and parametric formulation

ABSTRACT

In the present paper, the effect of joint geometry and collar plate size is investigated on the structural behavior of the strengthened X-joints subjected to compression. In the first step, the developed finite element (FE) model is verified using experimental data of six collar plate strengthened and un-strengthened X-joints conducted in the present authors’ previous study. After that, a total of 138 collar plate strengthened and un-strengthened FE models of tubular X-joints was conducted and analysed. Results show that the propagation of the plastic zone in strengthened connections with a big collar plate length is larger than the propagation of the plastic zone in strengthened connections with a small collar plate length. Finally, a theoretical equation is proposed based on the yield volume model to predict the ultimate capacity of X-connections strengthened with collar plates under brace compression.

KEYWORDS:

• Tubular X-connection
• collar plate
• ultimate compressive capacity
• initial stiffness
• failure patterns
• theoretical equation

Acknowledgements

The authors gratefully acknowledge the useful comments of anonymous reviewers on the draft version of this paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Dr. Hossein Nassiraei is Assistant professor of civil engineering at University of Guilan. His research interests mainly focus on the offshore structures and energy harnessing using the VIVACE converter.

Dr. Lei Zhu is professor of civil engineering at Beijing University of Civil Engineering and Architecture. His research interests are tubular structures, wind turbine towers and prefabricated structures.

Mr. Chen Gu is master graduate of Beijing University of Civil Engineering and Architecture. His research interest is tubular structures.

Additional information

Funding

Support from Beijing Advanced Innovation Center for Future Urban Design [grant number UDC2016030200], the National Natural Science Foundation of China [grant number 51778035], the JiandaJieqing Plan, and the Beijing Cooperative Innovation Research Center on Energy Saving and Emission Reduction are gratefully acknowledged.