Evaluation of the Stress Concentration Factor in Butt Welded Joints: A Comparative Study
Round 1
Reviewer 1 Report
The article has some minor revision (mostly text editing)
The clarity of the images can be improved
Author Response
Answer: Thank you for your comment.
The title has been re-written to “Evaluation of the stress concentration factor in butt welded joints: A comparative study”
Legend has been added to formula (1).
Paragraph 2.3 has been re-written to:
Static structural analyses of a weld seam-stress concentration were performed using FEM. The analyses are performed on the SalomeMeca 2018/CodeAster package, which allows for a wide variety of simulation scenarios and has a consistent list of verification cases.
The welded joint surface was scanned with a 3D scenario [8], and the obtained geometric model was imported to Salome Meca 2018 [21].
To prepare the surface data for meshing, cleaning of the mesh was required. Surface mesh triangles were adapted in order to obtain good volume mesh quality and surface irregularities, as holes and weld droplets were cleaned, as shown in Figure 5. Since the stress concentration is expected at the weld seam, the mesh is refined. Medium surface mesh has element length scaled-down 2 times, and coarse mesh 4 times.
Mesh convergence was checked in terms of maximum von Mises stress at three different sections (in the middle of each analyzed band, 25, 75, and 125 mm from the beginning of welding, respectively). The boundary conditions for the model are tensile forces perpendicular to the welded joint.
Legend has been added to each image of Figure 6.
- The tile for paragraph 4 has been re-written.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The authors claimed that they proposed a new method, however, it is purely based on curve fitting of a large number of data obtained by the well-known formula (1), then by omitting the other four parameter in formula (1), the authors get their ‘new’ fitted formula which contains one parameter. Therefore, I don't think there is any novelty in this paper, and I suggest it to be rejected.
Some useful suggestions are:
It is unclear what do the parameters in formula (1) represent. Which one represent the toe radius? And the toe radius, weld toe angle, weld width, thickness of the base material, and reinforcement height?
Author Response
Answer: Thank you for your comment.
The authors of the paper started working on this study using a well-known formula that contains 5 parameters, some of which are very challenging to analyze/measure. Our goal was to link this “old” formula in order to determine where an increased stress concentration might occur. The aim was to apply the formula (proposed by Ushirokawa and Mr. Nakayama) in practice. For this reason, a large number of experiments were performed; we compared the new formula with the old one (proposed by Ushirokawa and Mr. Nakayama). In the revised manuscript, we have more clearly explained the purpose and quality of this work.
Main revisions:
The title has been re-written to “Evaluation of the stress concentration factor in butt welded joints: A comparative study”
Legend has been added to formula (1).
Paragraph 2.3 has been re-written to:
Static structural analyses of a weld seam-stress concentration were performed using FEM. The analyses are performed on the SalomeMeca 2018/CodeAster package, which allows for a wide variety of simulation scenarios and has a consistent list of verification cases.
The welded joint surface was scanned with a 3D scenario [8], and the obtained geometric model was imported to Salome Meca 2018 [21].
To prepare the surface data for meshing, cleaning of the mesh was required. Surface mesh triangles were adapted in order to obtain good volume mesh quality and surface irregularities, as holes and weld droplets were cleaned, as shown in Figure 5. Since the stress concentration is expected at the weld seam, the mesh is refined. Medium surface mesh has element length scaled-down 2 times, and coarse mesh 4 times.
Mesh convergence was checked in terms of maximum von Mises stress at three different sections (in the middle of each analyzed band, 25, 75, and 125 mm from the beginning of welding, respectively). The boundary conditions for the model are tensile forces perpendicular to the welded joint.
Legend has been added to each image of Figure 6
- The tile for paragraph 4 has been re-written.
Author Response File: Author Response.pdf
Reviewer 3 Report
The paper investigates the evaluation of the SCF in butt welded joints. The paper does not provide a real new contribution in the field but it is interesting and can be considered for publication after major revisions. Comments are as follow:
- Parameters of Eq. 1 should be explained, and a picture should be inserted to better illustrate their meaning;
- It is not clear what is reported from lines 136 to 152;
- 3 is trivial and can be omitted;
- The authors should first indicate in Section 2.3 which FE code was used and then how the SCF was calculated from FEM results;
- What is the Salome software? Please explain;
- At line 204 it is not clear what are expressions 3a to d;
- In Fig. 6, a legend should be added to all figures;
- Please rename the tile of Section 4 as “Discussion and conclusions”
Author Response
- Parameters of Eq. 1 should be explained, and a picture should be inserted to better illustrate their meaning;
Answer: Thank you for your comment. Legend has been added to formula (1). In addition, we have added a new Figure 2, which clearly shows factors that affect the stress concentration
- It is not clear what is reported from lines 136 to 152;
Answer: Thank you for your comment. Line 136 and 152 were revised (section 2.3)
- 3 is trivial and can be omitted;
Answer: Figure 3 was removed from the manuscript.
- The authors should first indicate in Section 2.3 which FE code was used and then how the SCF was calculated from FEM results;
Answer: Section 2.3 was fully revised. The revised section clearly explains how to describe which FE code and how SCF was calculated.
- What is the Salome software? Please explain;
Answer: In section 2.3 we further described Salome Meca / Aster code.
- At line 204 it is not clear what are expressions 3a to d;
Answer: Expressions 3a-d are expressions for calculating the stress concentration factor depending on the weld toe angle.
- In Fig. 6, a legend should be added to all figures;
Answer: Legend has been added to each figures
- Please rename the tile of Section 4 as “Discussion and conclusions”
Answer: Section 4 was renamed, and the title has been re-written to “Evaluation of the stress concentration factor in butt welded joints: A comparative study”
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
I have no further comments
Reviewer 3 Report
The paper can be accepted for publication in the present form
