Journal of Structural and Construction Engineering

Journal of Structural and Construction Engineering

Experimental Comparison of the Behavior of Tensile Rebar Splices Using Coupler and Forge Welding

Document Type : Original Article

Authors
Hamed Karamlu 1
Mostafa Moghadasi 2
1 MSc,Faculty of Engineering, Bu-Ali Sina University, Hamedan, Iran.
2 Assistant professor, Faculty of Engineering, Bu-Ali Sina University, Hamedan, Iran.
10.22065/jsce.2025.498372.3623
Abstract
The use of alternative methods for the conventional method of lap splicing is inevitable. It can be referred to as coupler or gas pressure welding (GPW) with acceptable behavior in structural elements as an alternative method. Each standard coupler or GPW splice may be superior to each other in terms of different parameters. So, because of the lack of empirical studies in the field of comparing the behavior of the standard coupler and GPW splices, experimental research on this type of splice and the recognition of the advantages, and disadvantages of implementing each other is necessary. To this end, the experimental behavior of tensile rebar splices using couplers and GPW method was investigated. The rebars used in this study were of type S400. The total number of samples used in the experiments was 36. For each of rebars with 16, 18, 20, and 22 mm diameters, one sample was considered as non-spliced sample, four samples were considered coupler splices samples, and four other samples were considered GPW samples, with half of the spliced samples, without enclosure in concrete, and the other half of these samples were enclosed in concrete. A total of four samples without splices, 16 with mechanical splices, and 16 with GPW were considered for use in direct tensile testing and digital imaging correlation process. Various parameters were compared between coupler and GPW splices. For example, and on average, it can be said that the samples with coupler and GPW splices had a ductility reduction of about 19 and 29 percent, respectively, compared to the non-spliced samples, which indicates that the mechanical coupler is more ductile than GPW. Furthermore, on average, it can be said that samples with coupler and GPW splices had a 22 and 25 percent reduction in energy absorption, respectively, compared to non-spliced samples.
Keywords
Mechanical coupler splice
Gas pressure welding splice (GPW)
Stiffness
Absorbed energy
Ductility
Digital Image Correlation (DIC)

Subjects

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  • Receive Date 01 February 2025
  • Revise Date 09 June 2025
  • Accept Date 09 July 2025