Comparing Bolt Implementation Methods in Vibration Testing for Accurate Dynamic Behavior Analysis
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe manuscript deals with different strategies for describing bolted joints in simulations and the influences on the calculation accuracy. The work is of practical interest for corresponding investigations in the field of simulation. However, the following amendments are considered necessary before publication:
(1) The methods must be described in more detail and made more comprehensible:
(i) The exact difference between “screw” and “fixed bolt” (Figure 3 e, f) is not clear from the text and must be described better.
(ii) The procedure in Figure 4 is unclear and needs to be explained better. Was it an automated or manual process? Why does “Attach bolt thread” appear twice under a and b? In e and f, only “Search bolt” appears, but no further activity.
(iii) A coordinate system must be added to Figure 2.
(iv) In Figure 2, the height appears as 652.7 mm, but in the text it is 628.8 mm. Does this need to be corrected?
(v) For the description of the connections (lines 106-139), a figure reference is appropriate, e.g. “The bonded connection method (Figure 3a) establishes...”.
(vi) “RBE2” and “CBEAM” need to be explained in more detail (page 5).
(vii) The mesh size “5 mm” appears to be very large for an M6 screw (line 153). Here, the reader must be convinced that a meaningful mesh has been selected.
(viii) More information must be provided about the simulation model of the test jig. Element type, number of elements, material parameters, etc. The material “ALDC” must be described in more detail.
(ix) Which systems/devices/software were used to record the experimental values?
(x) The blue dashed lines in Figure 5 must be explained. Are these the positions of the sensors?
(2) The reason why the modes in Figure 8 were selected must be explained in a more comprehensible way. It is not entirely clear to the reader.
(3) The authors mention in the “Discussion” that preloads and friction were not taken into account. However, since it must initially be assumed that these can have an important influence, this must be discussed in more detail in order to convince the reader of the meaningfulness of the work carried out. Can existing scientific work be cited that indicates the influence of this simplification or can results of simplified models be presented?
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsDear Authors, I think it's good work. However, the following notes and modifications are suggested.
1. The abstract should be revised to show the novelty and mention the limitations, making it more interesting and more quantitative data.
2. Mesh generation has a major impact on the quality of the simulation data generated. It is necessary to offer mesh photos that show the coarse-to-fine mesh quality evolution.
3. The figure should be explained and referred to before it is mentioned in the text, e.g., figure 2.
4. There are simple mistakes. Try to put a space between the word and the reference, such as: ture[1,2], durability[3–5], .......etc. Try to correct the entire text.
5. There is a lack of clarity in the methodology section for selecting the 6 specific bolt connection methods.
6. There is no detailed consideration of bolt preload and contact friction coefficients.
7. In the section (2.1 Specifications): put a table containing the properties and dimensions is better than mentioning them in the text.
8. The study emphasizes the accuracy advantages of the joint connection method; however, it offers little information on computing efficiency when compared to alternative approaches.
9. I don't see the paper containing a conclusion section.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe authors presents the modeling methods of bolt connections for accurate dynamic behaviours. This topic is very important for engineering structures with bolts. The paper studied the accuracy of frequencies and mode shapes. The overall presentation of this paper is very good; however, before recommend for publication, it is suggested to consider the following issues:
1. It is suggested to clearly present the finite element models, including the meshes, element types, etc. The present figures only give their geometries;
2. As natural frequencies and mode shapes are considered (they are indeed very important); however, accurate dynamic behaviours also include the dynamic stress (10.2514/1.J058947). How to ensure the accuracy of dynamic stress in modeling methods of bolt connections? It is suggested to add some discussions.
3. A minor point: about the unit of acceleration, we usually use the lowercase letter (g).
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsDear Authors,
I would like to thank you for making the necessary modifications to the manuscript.
Reviewer 3 Report
Comments and Suggestions for AuthorsThe paper has been well revised and improved, it is suggested to publish.
